LIST PORT Release 56 Last change 21dec97
Copyright (c) 1989,1990,1991,1992,1993,1994,1995,1996,1997 Ralf Brown
[This file originally by Wim Osterholt <wim@djo.wtm.tudelft.nl>,
though it has grown considerably since.]
XT, AT and PS/2 I/O port addresses
Do NOT consider this information to be complete and accurate. If you want
to do hardware programming ALWAYS check the appropriate data sheets (but
even they are sometimes in error!). Be aware that erroneous port programming
can put your data or even your hardware at risk.
There are a number of memory-mapped addresses in use for I/O; see MEMORY.LST
for details on memory-mapped I/O.
--------!---Note-----------------------------
Note: the port description format is:
PPPPw RW description
where: PPPP is the four-digit hex port number
w is blank for byte-size port, 'w' for word, and 'd' for dword
R is blank or dash if not readable, 'r' if sometimes readable,
'R' if "always" readable, '?' if readability unknown
W is blank or dash if not writable, 'w' if sometimes writable,
'W' if "always" writable, '?' if writability unknown
----------P0000001F--------------------------
PORT 0000-001F - DMA 1 - FIRST DIRECT MEMORY ACCESS CONTROLLER (8237)
SeeAlso: PORT 0080h-008Fh"DMA",PORT 00C0h-00DFh
0000 R- DMA channel 0 current address byte 0, then byte 1
0000 -W DMA channel 0 base address byte 0, then byte 1
0001 RW DMA channel 0 word count byte 0, then byte 1
0002 R- DMA channel 1 current address byte 0, then byte 1
0002 -W DMA channel 1 base address byte 0, then byte 1
0003 RW DMA channel 1 word count byte 0, then byte 1
0004 R- DMA channel 2 current address byte 0, then byte 1
0004 -W DMA channel 2 base address byte 0, then byte 1
0005 RW DMA channel 2 word count byte 0, then byte 1
0006 R- DMA channel 3 current address byte 0, then byte 1
0006 -W DMA channel 3 base address byte 0, then byte 1
0007 RW DMA channel 3 word count byte 0, then byte 1
0008 R- DMA channel 0-3 status register (see #P001)
0008 -W DMA channel 0-3 command register (see #P002)
0009 -W DMA channel 0-3 write request register (see #P003)
000A RW DMA channel 0-3 mask register (see #P004)
000B -W DMA channel 0-3 mode register (see #P005)
000C -W DMA channel 0-3 clear byte pointer flip-flop register
any write clears LSB/MSB flip-flop of address and counter registers
000D R- DMA channel 0-3 temporary register
000D -W DMA channel 0-3 master clear register
any write causes reset of 8237
000E -W DMA channel 0-3 clear mask register
any write clears masks for all channels
000F rW DMA channel 0-3 write mask register (see #P006)
Notes: the temporary register is used as holding register in memory-to-memory
DMA transfers; it holds the last transferred byte
channel 2 is used by the floppy disk controller
on the IBM PC/XT channel 0 was used for the memory refresh and
channel 3 was used by the hard disk controller
on AT and later machines with two DMA controllers, channel 4 is used
as a cascade for channels 0-3
command and request registers do not exist on a PS/2 DMA controller
Bitfields for DMA channel 0-3 status register:
Bit(s) Description (Table P001)
7 channel 3 request active
6 channel 2 request active
5 channel 1 request active
4 channel 0 request active
3 channel terminal count on channel 3
2 channel terminal count on channel 2
1 channel terminal count on channel 1
0 channel terminal count on channel 0
SeeAlso: #P002,#P125
Bitfields for DMA channel 0-3 command register:
Bit(s) Description (Table P002)
7 DACK sense active high
6 DREQ sense active high
5 =1 extended write selection
=0 late write selection
4 rotating priority instead of fixed priority
3 compressed timing (two clocks instead of four per transfer)
=1 normal timing (default)
=0 compressed timing
2 =1 enable controller
=0 enable memory-to-memory
1-0 channel number
SeeAlso: #P001,#P004,#P005,#P126
Bitfields for DMA channel 0-3 request register:
Bit(s) Description (Table P003)
7-3 reserved (0)
2 =0 clear request bit
=1 set request bit
1-0 channel number
00 channel 0 select
01 channel 1 select
10 channel 2 select
11 channel 3 select
SeeAlso: #P004
Bitfields for DMA channel 0-3 mask register:
Bit(s) Description (Table P004)
7-3 reserved (0)
2 =0 clear mask bit
=1 set mask bit
1-0 channel number
00 channel 0 select
01 channel 1 select
10 channel 2 select
11 channel 3 select
SeeAlso: #P001,#P002,#P003,#P128
Bitfields for DMA channel 0-3 mode register:
Bit(s) Description (Table P005)
7-6 transfer mode
00 demand mode
01 single mode
10 block mode
11 cascade mode
5 direction
=0 address increment select
=1 address decrement select
3-2 operation
00 verify operation
01 write to memory
10 read from memory
11 reserved
1-0 channel number
00 channel 0 select
01 channel 1 select
10 channel 2 select
11 channel 3 select
SeeAlso: #P002,#P129
Bitfields for DMA channel 0-3 write mask register:
Bit(s) Description (Table P006)
7-4 reserved
3 channel 3 mask bit
2 channel 2 mask bit
1 channel 1 mask bit
0 channel 0 mask bit
Note: each mask bit is automatically set when the corresponding channel
reaches terminal count or an extenal EOP sigmal is received
SeeAlso: #P004,#P130
----------P0010001F--------------------------
PORT 0010-001F - DMA CONTROLLER (8237) ON PS/2 MODEL 60 & 80
SeeAlso: PORT 0000h-001Fh,PORT 0080h-008Fh"DMA",PORT 00C0h-00DFh
0018 -W extended function register (see #P007)
001A -W extended function execute register
Bitfields for DMA extended function register:
Bit(s) Description (Table P007)
7-4 function code (see #P008)
3 reserved (0)
2-0 channel number
000 channel 0 select
001 channel 1 select
010 channel 2 select
011 channel 3 select
100 channel 4 select
101 channel 5 select
110 channel 6 select
111 channel 7 select
(Table P008)
Values for DMA extended function codes (data go to/from PORT 001Ah):
Value Description Parameters Results
00h current address register - CA0,CA1
02h write address - A0,A1,P
03h read address A0,A1,P -
04h write word count register C0,C1 -
05h read word count register - C0,C1
06h read status register - S
07h mode register - M
09h mask channel - -
0Ah unmask channel - -
0Dh master clear - -
Note: CA0/CA1 LSB/MSB of the current address register
A0/A1 LSB/MSB of the base address register
P DMA page address
C0/C1 LSB/MSB of the word count register
S status register value (see #P001, #P125)
M mode register value (see #P005, #P129)
first, the extended function register is written, then the extended
function register execute register is read/written if the function
being executing requires
Bitfields for DMA extended mode register:
Bit(s) Description (Table P009)
7 reserved (0)
6 =0 8-bit transfer
=1 16-bit transfer
5-4 reserved (0)
3 transfer type
=0 read from memory
=1 write to memory
2 =0 disable memory write
=1 enable memory write
1 reserved (0)
0 address select
=0 use 0 as base address
=1 use a value from base address register
Note: the IBM PS/2 model 80 technical reference doesn't seem to mention this
register's address
----------P0020003F--------------------------
PORT 0020-003F - PIC 1 - PROGRAMMABLE INTERRUPT CONTROLLER (8259A)
SeeAlso: PORT 00A0h-00AFh"PIC 2",INT 08"IRQ0",INT 0F"IRQ7"
0020 -W PIC initialization command word ICW1 (see #P010)
0020 -W PIC output control word OCW2 (see #P015)
0020 -W PIC output control word OCW3 (see #P016)
0020 R- PIC interrupt request/in-service registers after OCW3
request register:
bit 7-0 = 0 no active request for the corresponding int. line
= 1 active request for corresponding interrupt line
in-service register:
bit 7-0 = 0 corresponding line not currently being serviced
= 1 corresponding int. line currently being serviced
0021 -W PIC ICW2,ICW3,ICW4 immed after ICW1 to 0020 (see #P011,#P012,#P013)
0021 RW PIC master interrupt mask register OCW1 (see #P014)
Bitfields for PIC initialization command word ICW1:
Bit(s) Description (Table P010)
7-5 0 (only used in 8080/8085 mode)
4 ICW1 is being issued
3 (LTIM)
=0 edge triggered mode
=1 level triggered mode
2 interrupt vector size
=0 successive interrupt vectors use 8 bytes (8080/8085)
=1 successive interrupt vectors use 4 bytes (80x86)
1 (SNGL)
=0 cascade mode
=1 single mode, no ICW3 needed
0 ICW4 needed
SeeAlso: #P011,#P012,#P013
Bitfields for PIC initialization command word ICW2:
Bit(s) Description (Table P011)
7-3 address lines A0-A3 of base vector address for PIC
2-0 reserved
SeeAlso: #P010,#P012,#P013
Bitfields for PIC initialization command word ICW3:
Bit(s) Description (Table P012)
7-0 =0 slave controller not attached to corresponding interrupt pin
=1 slave controller attached to corresponding interrupt pin
SeeAlso: #P010,#P011,#P013
Bitfields for PIC initialization command word ICW4:
Bit(s) Description (Table P013)
7-5 reserved (0)
4 running in special fully-nested mode
3-2 mode
0x nonbuffered mode
10 buffered mode/slave
11 buffered mode/master
1 Auto EOI
0 =0 8085 mode
=1 8086/8088 mode
SeeAlso: #P010,#P011,#P012
Bitfields for PIC output control word OCW1:
Bit(s) Description (Table P014)
7 disable IRQ7 (parallel printer interrupt)
6 disable IRQ6 (diskette interrupt)
5 disable IRQ5 (fixed disk interrupt)
4 disable IRQ4 (serial port 1 interrupt)
3 disable IRQ3 (serial port 2 interrupt)
2 disable IRQ2 (video interrupt)
1 disable IRQ1 (keyboard, mouse, RTC interrupt)
0 disable IRQ0 (timer interrupt)
SeeAlso: #P015,#P016,#P124
Bitfields for PIC output control word OCW2:
Bit(s) Description (Table P015)
7-5 operation
000 rotate in auto EOI mode (clear)
001 (WORD_A) nonspecific EOI
010 (WORD_H) no operation
011 (WORD_B) specific EOI
100 (WORD_F) rotate in auto EOI mode (set)
101 (WORD_C) rotate on nonspecific EOI command
110 (WORD_E) set priority command
111 (WORD_D) rotate on specific EOI command
4-3 reserved (00 - signals OCW2)
2-0 interrupt request to which the command applies
(only used by WORD_B, WORD_D, and WORD_E)
SeeAlso: #P014,#P016
Bitfields for PIC output control word OCW3:
Bit(s) Description (Table P016)
7 reserved (0)
6-5 special mask
0x no operation
10 reset special mask
11 set special mask mode
4-3 reserved (01 - signals OCW3)
2 poll command
1-0 function
0x no operation
10 read interrupt request register on next read from PORT 0020h
11 read interrupt in-service register on next read from PORT 0020h
Note: the special mask mode permits all other interrupts (even those with
lower priority) to be processed while an interrupt is already in
service, but will not re-issue an interrupt for a particular IRQ
while it remains in service
SeeAlso: #P014,#P015
----------P00220023--------------------------
PORT 0022-0023 - CHIP SET DATA
Note: These two ports are used by numerous chipsets. Various chipsets are
detailed below.
0022 -W index for accesses to data port
0023 RW chip set data
----------P00220023--------------------------
PORT 0022-0023 - Cyrix Cx486SLC/DLC PROCESSOR - CACHE CONFIGURATION REGISTERS
SeeAlso: PORT 0022h"5x86",PORT 0022h"6x86"
0022 -W index for accesses to next port (see #P017)
0023 RW cache configuration register array (indexed by PORT 0022h)
Note: the index must be written to PORT 0022h before every access
to PORT 0023h; out-of-sequence accesses or index values
not supported by the processor generate external I/O cycles
(Table P017)
Values for Cyrix Cx486SLC/DLC Cache Configuration register number:
C0h CR0 (see #P019)
C1h CR1 (see #P020)
C4h non-cacheable region 1, start address bits 31-24
C5h non-cacheable region 1, start address bits 23-16
C6h non-cacheable region 1, start addr 15-12, size (low nibble) (see #P018)
C7h non-cacheable region 2, start address bits 31-24
C8h non-cacheable region 2, start address bits 23-16
C9h non-cacheable region 2, start addr 15-12, size (low nibble) (see #P018)
CAh non-cacheable region 3, start address bits 31-24
CBh non-cacheable region 3, start address bits 23-16
CCh non-cacheable region 3, start addr 15-12, size (low nibble) (see #P018)
CDh non-cacheable region 4, start address bits 31-24
CEh non-cacheable region 4, start address bits 23-16
CFh non-cacheable region 4, start addr 15-12, size (low nibble) (see #P018)
SeeAlso: #P023,#P021
(Table P018)
Values for Cyrix Cx486SLC/DLC non-cacheable region sizes:
00h disabled
01h 4K
02h 8K
03h 16K
04h 32K
05h 64K
06h 128K
07h 256K
08h 512K
09h 1M
0Ah 2M
0Bh 4M
0Ch 8M
0Dh 16M
0Eh 32M
0Fh 4G
SeeAlso: #P017
Bitfields for Cyrix Cx486SLC/DLC Configuration Register 0:
Bit(s) Description (Table P019)
0 "NC0" first 64K of each 1M noncacheable in real/V86
1 "NC1" 640K-1M noncacheable
2 "A20M" enables A20M# input pin
3 "KEN" enables KEN# input pin
4 "FLUSH" enables FLUSH input pin
5 "BARB" enables internal cache flushing on bus holds
6 "C0" cache direct-mapped instead of 2-way associative
7 "SUSPEND" enables SUSP# input and SUSPA# output pins
SeeAlso: #P017,#P020,#P032
Bitfields for Cyrix Cx486SLC/DLC Configuration Register 1:
Bit(s) Description (Table P020)
0 "RPL" enables output pins RPLSET and RPLVAL#
SeeAlso: #P017,#P019,#P024
----------P00220023--------------------------
PORT 0022-0023 - Cyrix 486S2/D2/DX/DX2/DX4 PROCESSOR - CONFIGURATION REGISTERS
SeeAlso: PORT 0022h"Cx486SLC",PORT 0022h"5x86",PORT 0022h"6x86"
0022 -W index for accesses to next port (see #P021)
0023 RW cache configuration register array (indexed by PORT 0022h)
Note: the index must be written to PORT 0022h before every access
to PORT 0023h; out-of-sequence accesses or index values
not supported by the processor generate external I/O cycles
(Table P021)
Values for Cyrix 486S2/D2/DX/DX2/DX4 configuration register number:
C2h CR2 (see #P025)
C3h CR3 (see #P026)
CDh SMM region, start address bits 31-24
CEh SMM region, start address bits 23-16
CFh SMM region, start addr 15-12, size (low nibble) (see #P018)
FEh R Device Identification #0 (see #P022)
CPU device ID
FFh R Device Identification #1
bits 3-0: revision
bits 7-4: stepping
SeeAlso: #P017,#P023,#P031
(Table P022)
Values for Cyrix device identification:
(#0 /#1)
00h Cx486SLC
01h Cx486DlC
02h Cx486SLC2
03h Cx486DLC2
04h Cx486SRx
05h Cx486DRx
06h Cx486SRx2
07h Cx486DRx2
10h Cx486S (B-step)
11h Cx486S2 (B-step)
12h Cx486Se (B-step)
13h Cx486S2e (B-step)
1Ah/05h Cx486DX-40
1Bh/08h Cx486DX2-50
1Bh/0Bh Cx486DX2-66
1Bh/31h Cx486DX2-v80
1Fh/36h Cx486DX4-v100
28h 5x86 1xs
29h 5x86 2xs
2Ah 5x86 1xp
2Bh 5x86 2xp
2Ch 5x86 4xs
2Dh 5x86 3xs
2Eh 5x86 4xp
2Fh 5x86 3xp
30h 6x86 1xs
31h 6x86 2xs
32h 6x86 1xp
33h 6x86 2xp
34h 6x86 4xs
35h 6x86 3xs
36h 6x86 4xp
37h 6x86 3xp
Note: #0 is the value in configuration register FEh, while #1 is the value
in configuration register FFh
SeeAlso: #P021
----------P00220023--------------------------
PORT 0022-0023 - Cyrix 5x86 PROCESSOR - CONFIGURATION CONTROL REGISTERS
SeeAlso: PORT 0022h"Cx486SLC",PORT 0022h"486S2",PORT 0022h"6x86"
0022 -W index for accesses to next port (see #P023)
0023 RW configuration control register array (indexed by PORT 0022h)
Note: the index must be written to PORT 0022h before every access
to PORT 0023h; out-of-sequence accesses or index values
not supported by the processor generate external I/O cycles
(Table P023)
Values for Cyrix 5x86 configuration registers:
20h Performance Control (see #P028)
C1h Configuration Control #1 (CCR1) (see #P024)
C2h Configuration Control #2 (CCR2) (see #P025)
C3h Configuration Control #3 (CCR3) (see #P026)
CDh System Memory Management address region #0 (smar0) (see #P029)
CEh System Memory Management address region #1 (smar1)
CFh System Memory Management address region #2 (smar2)
E8h Configuration Control Register 4
F0h Power Management (see #P030)
FEh R Device Identification #0 (see #P022)
CPU device ID
FFh R Device Identification #1
bits 3-0: revision
bits 7-4: stepping
SeeAlso: #P017,#P021,#P031
Bitfields for Cyrix 5x86,6x86 Configuration Control Register 1 (CCR1):
Bit(s) Description (Table P024)
0 reserved
1 enable SMM pins
2 system management memory access
3 main memory access
4 (6x86) no LOCK during bus cycles
6-5 reserved
7 (6x86) use address region 3 as SMM space
Note: bits 1,2,7 may only be written when CCR3 bit 0 is enabled
SeeAlso: #P020,#P025,#P026,#P027
Bitfields for Cyrix 5x86,6x86 Configuration Control Register 2 (CCR2):
Bit(s) Description (Table P025)
0 reserved
1 enable write-back cache interface pins
2 lock NW bit
3 suspend on HLT instruction
4 write-through region 1
5 reserved
6 enable burst write cycles
7 enable suspend pins
SeeAlso: #P024,#P026,#P027
Bitfields for Cyrix 5x86,6x86 Configuration Control Register 3 (CCR3):
Bit(s) Description (Table P026)
0 SMM register lock (can only be cleared in SMM mode or by CPU reset)
1 NMI enable
2 linear address burst cycles (5x86,6x86 only)
=0 Pentium-compatible
=1 linear sequencing
3 SMM mode (5x86 only)
=0 486SL
=1 Cyrix
7-4 map enable (5x86,6x86 only)
0000 only allow access to configuration registers C0h-CFh,FEh,FFh
0001 enable access to all configuration registers
SeeAlso: #P024,#P025,#P027,#P028,#P030
Bitfields for Cyrix 5x86,6x86 Configuration Control Register 4 (CCR4):
Bit(s) Description (Table P027)
2-0 I/O recovery time (000 = none, else 2^N clocks)
3 enable memory-read bypassing (5x86 only)
4 enable directory table entry cache
6-5 reserved
7 enable CPUID instruction (stepping 1+ and Cx6x86)
Note: this register is only accessible when bits 7-4 of CCR3 are 0001
SeeAlso: #P024,#P025,#P026
Bitfields for Cyrix 5x86 Performance Control register:
Bit(s) Description (Table P028)
0 return stack enabled (speculatively execute code after current CALL)
1 branch-target buffer enabled
2 loop enable
6-3 reserved (0)
7 load-store serialization enabled
(memory reads and writes may be reorganized into optimum order)
Note: this register is only accessible when bits 7-4 of CCR3 are 0001
SeeAlso: #P030,#P024
Bitfields for Cyrix 5x86 SMM Address Region register:
Bit(s) Description (Table P029)
3-0 block size
23-4 starting address
Bitfields for Cyrix 5x86 Power Management register:
Bit(s) Description (Table P030)
1-0 core clock to bus clock ratio
00 1:1
01 2:1
10 reserved
11 3:1
2 CPU running at half bus speed, ignore bits 1-0
Note: this register is only accessible when bits 7-4 of CCR3 are 0001
----------P00220023--------------------------
PORT 0022-0023 - Cyrix 6x86 PROCESSOR - CONFIGURATION CONTROL REGISTERS
SeeAlso: PORT 0022h"Cx486",PORT 0022h"5x86"
0022 -W index for accesses to next port (see #P023)
0023 RW configuration control register array (indexed by PORT 0022h)
Note: the index must be written to PORT 0022h before every access
to PORT 0023h; out-of-sequence accesses or index values
not supported by the processor generate external I/O cycles
(Table P031)
Values for Cyrix 6x86 configuration registers:
C0h Configuration Control Register 0 (CCR0) (see #P032)
C1h Configuration Control #1 (CCR1) (see #P024)
C2h Configuration Control #2 (CCR2) (see #P025)
C3h Configuration Control #3 (CCR3) (see #P026)
C4h Address region 0 (bits 31-24)
C5h Address region 0 (bits 23-16)
C6h Address region 0 (bits 15-12 and size)
C7h Address region 1 (bits 31-24)
C8h Address region 1 (bits 23-16)
C9h Address region 1 (bits 15-12 and size)
CAh Address region 2 (bits 31-24)
CBh Address region 2 (bits 23-16)
CCh Address region 2 (bits 15-12 and size)
CDh Address region 3 (bits 31-24)
CEh Address region 3 (bits 23-16)
CFh Address region 3 (bits 15-12 and size)
D0h Address region 4 (bits 31-24)
D1h Address region 4 (bits 23-16)
D2h Address region 4 (bits 15-12 and size)
D3h Address region 5 (bits 31-24)
D4h Address region 5 (bits 23-16)
D5h Address region 5 (bits 15-12 and size)
D6h Address region 6 (bits 31-24)
D7h Address region 6 (bits 23-16)
D8h Address region 6 (bits 15-12 and size)
D9h Address region 7 (bits 31-24)
DAh Address region 7 (bits 23-16)
DBh Address region 7 (bits 15-12 and size)
DCh Region Control 0
DDh Region Control 1
DEh Region Control 2
DFh Region Control 3
E0h Region Control 4
E1h Region Control 5
E2h Region Control 6
E3h Region Control 7
E8h Configuration Control Register 4 (see #P027)
E9h Configuration Control Register 5 (see #P033)
FEh R Device Identification #0 (see #P022)
CPU device ID
FFh R Device Identification #1
bits 3-0: revision
bits 7-4: stepping
SeeAlso: #P017,#P023
Bitfields for Cyrix 6x86 Configuration Control Register 0:
Bit(s) Description (Table P032)
7-2 ???
1 address region 640K-1M is noncacheable
0 ???
SeeAlso: #P019
Bitfields for Cyrix 6x86 Configuration Control Register 5:
Bit(s) Description (Table P033)
7-6 reserved
5 enable all address-region registers (control registers C4h-DBh)
4 assert LBA# pin on all accesses to 640K-1M
3-1 reserved
0 allocate new cache lines only on read misses
SeeAlso: #P032,#P027,#P031
--------X-P00220023--------------------------
PORT 0022-0023 - Intel 82358DT 'Mongoose' EISA CHIPSET - 82359 DRAM CONTROLLER
Notes: this chip uses a chip ID of 01
the LIM register herein use a chip ID of 1A
Index: Intel 82351
0022 -W index for accesses to data port (see #P035,#P036,#P037)
0023 RW chip set data
(Table P034)
Values for Intel 82351/82359 chip ID:
01h 82359 DRAM controller, general registers
02h 82351 EISA local I/O support
A1h 82359 DRAM controller, EMS registers
FFh no chip accessible (default)
SeeAlso: #P035,#P036,#P037
(Table P035)
Values for 82359 DRAM controller general register index:
00h DRAM bank 0 type
bit 7 unknown
bit 6-4 000 DRAM in bank 0 (standard)
001 bank 1
010 bank 2
011 bank 3
100 banks 0,1
101 banks 2,3
110 banks 0,1,2,3
111 empty (standard for 1,2,3)
bit 3-2 unknown
bit 1-0 00 64K chips used
01 256K
10 1M
11 4M
01h DRAM bank 1 type
02h DRAM bank 2 type
03h DRAM bank 3 type
04h DRAM speed detection/selection
05h DRAM interleave control
06h RAS line mode
07h cache-enable selection
08h mode register A (DRAM, cache)
09h mode register B (cache, burst modes, BIOS size)
0Ah mode register C (concurrency control, burst/cycle speed)
10h host timing
11h host-system delay timing
12h system timing
13h DRAM row precharge time
14h DRAM row timing
15h DRAM column timing
16h CAS pulse width
17h CAS-to-MDS delay
21h chip ID register -- selects which chip responds on these ports
(see #P034)
28h-2Ch parity-error trap address
30h page hit cycle length (read)
31h page miss cycle length (read)
32h row miss cycle length (read)
33h page hit cycle length (write)
34h page miss cycle length (write)
35h row miss cycle length (write)
40h memory enable 00000h-7FFFFh
41h memory enable 80000h-9FFFFh
42h memory enable A0000h-AFFFFh
43h memory enable B0000h-BFFFFh
44h memory enable C0000h-CFFFFh
45h memory enable D0000h-DFFFFh
46h memory enable E0000h-EFFFFh
47h memory enable F0000h-FFFFFh
4Eh remap 80000h-FFFFFh to extended memory
50h-53h programmable attribute map 1
54h-57h programmable attribute map 2
58h-5Bh programmable attribute map 3
5Ch-5Fh programmable attribute map 4
83h-84h split address register (address bits A31-A20)
85h cache control
8Bh system throttle
8Ch host throttle
8Dh host memory throttle watchdog
8Eh host system throttle
8Fh host system throttle watchdog
90h RAM enable
91h RAM disable
92h-93h elapsed-time registers
94h-95h host memory ownership request
96h-97h system memory ownership request
98h-99h host memory ownership
9Ah-9Bh system bus ownership
9Ch-9Dh host system bus request
9Eh-9Fh memory ownership transfer
SeeAlso: #P036,#P037
(Table P036)
Values for Intel 82359 DRAM controller EMS register index:
00h EMS cotnrol
21h chip ID register -- selects which chip responds on these ports
(see #P034)
80h-8Fh EMS page registers, pages 0-7
SeeAlso: #P035,#P037
(Table P037)
Values for Intel 82351 EISA Local I/O register index:
21h chip ID register -- selects which chip responds on these ports
(see #P034)
C0h peripheral enable register A
C1h peripheral enable register B
C2h parallel configuration register
C3h serial configuration register A
C4h floppy disk controller configuration register
C5h serial configuration register B
C6h COM3 port address (low)
C7h COM3 port address (high)
C8h COM4 port address (low)
C9h COM4 port address (high)
D0h-D3h general chip select lines 0-3 (mask registers)
D4h-D7h general chip select line addresses 0-3 (low bytes)
D8h-DBh general chip select line addresses 0-3 (high bytes)
DCh extended CMOS RAM page port address (low)
DDh extended CMOS RAM page port address (high)
DFh extended CMOS RAM access select address (high byte)
E8h-EBh EISA ID configuration registers (reflect at PORT 0C80h)
SeeAlso: #P035,#P036
--------X-P00220023--------------------------
PORT 0022-0023 - Intel 82374EB/SB EISA CHIPSET
Index: Intel 82374EB;Intel 82374SB
0022 -W index for accesses to data port (see #P038)
0023 RW chip set data
(Table P038)
Values for Intel 82374 register index:
02h ESC identification register
(82374 will only respond to ports 0022h and 0023h after an 0Fh
is written to this register)
!!!29047604.pdf pg. 36
08h revision ID register
40h mode select
42h BIOS Chip Select A
43h BIOS Chip Select B
4Dh EISA clock divisor
4Eh peripheral Chip Select A
4Fh peripheral Chip Select B
50h-53h EISA ID registers
57h scatter/gather relocate base address (see also #0871)
(specifies bits 15-0 if S/G port addresses [low byte always 10h-3Fh])
59h APIC base address relocation
60h-63h PCI IRQn# route control (see also #0872)
64h general-purpose chip select low address 0
65h general-purpose chip select high address 0
66h general-purpose chip select mask register 0
68h general-purpose chip select low address 1
69h general-purpose chip select high address 1
6Ah general-purpose chip select mask register 1
6Ch general-purpose chip select low address 2
6Dh general-purpose chip select high address 2
6Eh general-purpose chip select mask register 2
6Fh general-purpose peripheral X-Bus control
---SB only---
70h PCI/APIC control
88h test control
A2h-A3h SMI enable
A4h-A7h System Event Enable
A8h Fast-Off timer
AAh-ABh SMI Request
ACh Clock Scale STPCLK# low timer
AEh Clock Scale STPCLK# high timer
----------P00220023--------------------------
PORT 0022-0023 - CHIPSET FROM ETEC CHEETAH ET6000 (SINGLE CHIP)
0022 RW chip set data
0023 ?W index for accesses to data port (see #P039)
(Table P039)
Values for Etec Cheetah ET6000 chip set register index:
10h system configuration register (see #P040)
11h cache configuration & non-cacheable block size register (see #P041)
12h non-cacheable block address register
bit 7-1 non-cacheable address, A25-A19
bit 0 reserved
13h DRAM bank & type configuration register (see #P042)
14h DRAM configuration register (see #P043)
15h shadow RAM configuration register (see #P044)
Bitfields for Etec Cheetah ET6000 system configuration register:
Bit(s) Description (Table P040)
7-6 00 turbo/non-turbo
01 local device supported
10 suspend mode
11 illegal
5 reserved
4 refresh selection
0 = AT type refresh
1 = concurrent refresh
3 slow refresh 95mSec enabled
2 fast reset delay
0 = do not use delay
1 = wait for 2mSec delay
1 wait for HALT after KBDRST
0 RAM at A0000-BFFFF
0 = AT bus cycle
1 = local bus cycle
SeeAlso: #P039
Bitfields for Etec Cheetah ET6000 cache configuration register:
Bit(s) Description (Table P041)
7-5 000 disabled
001 512K
010 1M
011 2M
100 4M
101 8M
110 16M
111 32M
4 DRAM banks
0 = 2-bank DRAM
1 = 4-bank DRAM
3-0 reserved
SeeAlso: #P039
Bitfields for Etec Cheetah ET6000 DRAM bank & type configuration register:
Bit(s) Description (Table P042)
7-6 bank 3 DRAM type
00 none
01 256K
10 1M
11 4M
5-4 bank 2 DRAM type
3-2 bank 1 DRAM type
1-0 bank 0 DRAM type
SeeAlso: #P039
Bitfields for Etec Cheetah ET6000 DRAM configuration register:
Bit(s) Description (Table P043)
7 on-board memory range 15M to 16M disabled
6 on-board memory range 512K-640K disabled
5 ROM chip select at C0000-DFFFF enabled
4 RAS to CAS time
0 = 1 SYSCLCK, not for R0WS
1 = 2 SYSCLCK
3 RAS precharge time
0 = 1.5 SYSCLCK
1 = 2.5 SYSCLCK
2-1 read cycle wait state
00 = 0 wait state
01 = 1 ws
10 = 2 ws
11 = 3 ws
0 write cycle wait state
0 = 0 ws
1 = 1 ws
SeeAlso: #P039
Bitfields for Etec Cheetah ET6000 shadow RAM configuration register:
Bit(s) Description (Table P044)
7 shadow at C0000-FFFFF
0 = non-cacheable
1 = cacheable and cache-write-proteced
6 access ROM/RAM at F0000-FFFFF
0 = read from ROM, write to RAM
1 = read from shadow, write is protected
5 access ROM/RAM at E0000-EFFFF
0 = access on-board ROM, AT bus cycle
1 = access shadow E0000-EFFFF enabled
4 RAM at E0000-EFFFF is read-only
3 access ROM/RAM at D0000-DFFFF
0 = access on-board ROM, AT bus cycle
1 = access shadow D0000-DFFFF enabled
2 RAM at D0000-DFFFF is read-only
1 access ROM/RAM at C0000-CFFFF
0 = access on-board ROM, AT bus cycle
1 = access shadow C0000-CFFFF enabled
0 RAM at C0000-CFFFF is read-only
SeeAlso: #P039
----------P00220023--------------------------
PORT 0022-0023 - Hewlett-Packard Hornet chipset (HP 100LX/200LX)
0022 RW index for accesses to data port (see Table P189)
0023 RW chip set data
(Table P045)
Values for HP Hornet chipset register index:
1Eh buzzer volume/clock oscillator speed
bit 7-6: buzzer volume
bit 5-4: system oscillator speed
00: 10.738636MHz
01: 15.836773MHz(HP 100/200LX has oscillator with this speed)
10: 21.477272MHz
11: 31.673550MHz
21h display timing???
23h LCD contrast (see INT15h AH=62h)
valid values: 00h-1fh (1fh is the darkest)
51h power adapter status
bit 7-1: ???
bit 0: power adapter status(0=inactive/1=active)
52h nicad charge status
bit 7-3: ???
bit 2: battery charging status(0=???/1=slow charge)
bit 1-0: ???
53h nicad charge status
bit 7-1: ???
bit 0: battery charging status(0=???/1=fast charge)
80h memory wait for internal ROM
valid values: 00h-07h
81h memory wait for internal RAM
valid values: 00h-03h
82h memory wait for external RAM
valid values: 00h-0fh
87h battery status???
----------P00220023--------------------------
PORT 0022-0023 - OPTi 82C206 chipset - CONFIGURATION REGISTERS
Note: many other OPTi chipsets integrate the functionality of the 82C206, and
thus support the 82C206's configuration register (e.g. the
82C558 from the Viper chipset)
0022 ?W index for accesses to data port (set to 01h)
0023 RW chip set data
Bitfields for OPTi 82C206 configuration register 01h:
Bit(s) Description (Table P046)
7-6 82C206 wait states
00 1 SYSCLK
01 2 SYSCLKs
10 3 SYSCLKs
11 4 SYSCLKs (default)
5-4 number of wait states for 16-bit DMA cycles
00 1 wait state (default)
01 2 wait states
10 3 wait states
11 4 wait states
3-2 number of wait states for 8-bit DMA cycles
00 1 wait state (default)
01 2 wait states
10 3 wait states
11 4 wait states
1 enable early DMAMEMR#
0 DMA speed
0 SYSCLK/2
1 SYSCLK
----------P00220024--------------------------
PORT 0022-0024 - CHIPSET FROM PICO POWER, UMC or PCChips
0022 ?W index for accesses to data port
0024 RW chip set data
----------P00220024--------------------------
PORT 0022-0024 - OPTi 82C281/282/283 CHIPSETS - CONFIGURATION REGISTERS
Note: every access to PORT 0024h must be preceded by a write to PORT 0022h,
even if the same register is being accessed a second time
SeeAlso: PORT 0022h"82C206"
0022 ?W index for accesses to data port (see #P047)
0024 RW chip set data
(Table P047)
Values for OPTi 82C281/82C282/82C283 configuration register index:
10h DRAM configuration register (see #P048)
11h Shadow RAM control register (see #P049)
12h Shadow RAM control register 2 (see #P050)
13h Shadow RAM control register 3 (see #P051)
14h miscellaneous control register (see #P052)
15h cache control register (see #P053)
16h cache control register 2 (see #P054)
Bitfields for OPTi 82C281/282/283 DRAM configuration register:
Bit(s) Description (Table P048)
7-6 82C281/2 revision number (read-only)
7 82C283 revision (0 = A, 1 = B)
6 82C283A: reserved
82C283B: DRAM is pipelined
5 local DRAM read wait states
82C281/2: 0=one, 1=two 82C283: 0=none, 1=one
4 local DRAM write wait states
82C281/2: 0=one, 1=two 82C283: 0=none, 1=one
3-0 local DRAM memory configuration
(val) Bank0 Bank1 Bank2 Bank3
0001 256K 256K 256K 256K
0010 256K 256K 1M -
0011 256K 256K 1M 1M
0100 256K 256K 4M -
0101 1M - - -
0110 1M 1M - -
0111 1M 1M 1M -
1000 1M 1M 1M 1M
1001 1M 4M - -
1010 1M 1M 4M -
1011 4M 4M - -
1100 4M - - - (82C283B only)
1111 256K 256K - -
SeeAlso: #P047
Bitfields for OPTi 82C281 shadow RAM control register:
Bit(s) Description (Table P049)
7 BIOS ROM F000-FFFF shadowing
0 read-only from shadow RAM
1 read from ROM, write to shadow RAM
6 adapter ROM at E000-EFFF
0 disable shadow RAM
1 shadow RAM selectively enabled by configuration register 12h
(see #P050)
5 adapter ROM at D000-DFFF
0 disable shadow RAM
1 shadow RAM selectively enabled by configuration register 12h
4 adapter ROM at C000-CFFF
0 disable shadow RAM
1 shadow RAM selectively enabled by configuration register 13h
(see #P051)
3 shadow RAM Copy Enable control (C000-EFFF)
0 write to expansion bus
1 write to local DRAM
2 shadow RAM E000-EFFF writeability
0 read/write
1 read-only
1 shadow RAM D000-DFFF writeability
0 read/write
1 read-only
0 shadow RAM C000-CFFF writeability
0 read/write
1 read-only
SeeAlso: #P047,#P050
Bitfields for OPTi 82C281 shadow RAM control register 2:
Bit(s) Description (Table P050)
7 enable EC00-EFFF
6 enable E800-EBFF
5 enable E400-E7FF
4 enable E000-E3FF
3 enable DC00-DFFF
2 enable D800-DBFF
1 enable D400-D7FF
0 enable D000-D3FF
Note: bits 7-4 are only in effect when register 11h bit 6 is set; bits 3-0
are only in effect when register 11h bit 5 is set
SeeAlso: #P047,#P049,#P051
Bitfields for OPTi 82C281 shadow RAM control register 3:
Bit(s) Description (Table P051)
7 enable CC00-CFFF
6 enable C800-CBFF
5 enable C400-C7FF
4 enable C000-C3FF
3-0 unused shadow RAM remap address; supplies bits 23-20 of
address at which to map A000-BFFFF and D000-EFFF is not used
for shadowing (except if this field is set to 0, the remapping
is disabled)
SeeAlso: #P047,#P049,#P050
Bitfields for OPTi 82C281 miscellaneous control register:
Bit(s) Description (Table P052)
7 allow F0000-F0FFF to be written even while F0000-FFFFF is
write-protected ("Zenith mode")
6 keyboard reset control
=1 HLT must be executed before 82C281 generates CPU reset from
keyboard controller Reset command
5 master byte swap enable
4 82C281/2: fast NMI request
82C283A: reserved (0)
82C283B: ATCLK setting (=0 from register 14h bit 0; =1 CLK/8)
3 82C281/2/3A: reserved
82C283B: on-board DRAM parity error enable
2 enable slow refresh mode
(every 95.5 us (281/282) or 63.6 us (283) instead of 15.9 us)
1 enable turbo switch function
0 clock select
=0 ATCLK2 = CPUCLK2 / 6
=1 ATCLK2 = CPUCLK2 / 4
SeeAlso: #P047
Bitfields for OPTi 82C281/82C282 cache control register:
Bit(s) Description (Table P053)
7 enable cache
6 reserved (0)
5 enable posted write (82C281 only)
4 ALL accesses are non-cacheable
3 reserved (0)
2-0 non-cacheable region size (see also #P054)
000 64K
001 128K
...
101 4M
110 8M
111 disabled
SeeAlso: #P047,#P054
Bitfields for OPTi 82C281/82C282 cache control register 2:
Bit(s) Description (Table P054)
7-0 starting address bits 23-16 of non-cacheable region
Note: the specified starting address must be a multiple of the region size
SeeAlso: #P047,#P053
----------P00220024--------------------------
PORT 0022-0024 - OPTi 82C291/82C295 CHIPSETS - CONFIGURATION REGISTERS
Note: every access to PORT 0024h must be preceded by a write to PORT 0022h,
even if the same register is being accessed a second time
SeeAlso: PORT 0022h"82C206"
0022 ?W index for accesses to data port (see #P055)
0024 RW chip set data
(Table P055)
Values for OPTi 82C291/82C295 configuration register index:
20h Revision/AT Bus configuration register (see #P056)
21h System Control register (see #P)
22h DRAM configuration register (see #P)
23h ROM Chip Select Control register (see #P)
24h Shadow RAM control register E (see #P)
25h Shadow RAM control register D (see #P)
26h Shadow RAM control register C (see #P)
27h Shadow RAM Write Protect/Remap Area (see #P)
28h Cache Control register (see #P)
29h Cacheable Upper Bound register (see #P)
2Ah Non-Cacheable Segments register 1 (see #P)
2Bh Non-Cacheable Segments register 2 (see #P)
2Ch Non-Cacheable Segments register 3 (see #P)
Bitfields for OPTi 82C291/82C295 AT Bus configuration register:
Bit(s) Description (Table P056)
7-6 82C291/295 revision (read-only)
5-4 back-to-back I/O recovery time
00-11 = 3-6 ATCLKs between I/O accesses
3 enable slow refresh mode
2 enable hidden refresh
1-0 AT clock selection
00 ATCLK = CLK2 / 10
01 ATCLK = CLK2 / 8
10 ATCLK = CLK2 / 6
11 ATCLK = CLK2 / 4
SeeAlso: #P055
Bitfields for OPTi 82C291/82C295 System Control register:
Bit(s) Description (Table P057)
7 AT bus master byte swap enabled
6 !!!db011_10.pdf p.20
SeeAlso: #P055
----------P00220024--------------------------
PORT 0022-0024 - OPTi 82C381/82C382 CHIPSETS - CONFIGURATION REGISTERS
Note: every access to PORT 0024h must be preceded by a write to PORT 0022h,
even if the same register is being accessed a second time
SeeAlso: PORT 0022h"82C206"
0022 ?W index for accesses to data port (see #P058)
0024 RW chip set data
(Table P058)
Values for OPTi 82C381/82C382 configuration register index:
00h clock selects (see #P059)
01h reset control (see #P060)
10h remapping address (see #P061)
11h shadow RAM (see #P062)
12h memory enable (see #P063)
13h bank configuration (see #P064)
14h DRAM configuration (see #P065)
15h video adapter shadow (see #P066)
16h fast GateA20 (see #P067)
17h cache configuration (see #P068)
18h non-cacheable block 1 size (see #P069)
19h non-cacheable block 1 address (see #P070)
1Ah non-cacheable block 2 size (see #P069)
1Bh non-cacheable block 2 address (see #P070)
1Ch cacheable area (see #P071)
Note: registers 00h and 01h address the 82C381, the remaining registers
address the 82C382
Bitfields for OPTi 82C381/82C382 clock selects:
Bit(s) Description (Table P059)
7-6 cache controller enable
00 cache controller disabled (default)
01 cache controller disabled; PPCS#, SPCS#, NPCS# signals are
active if selected
10 external cache controller installed
11 on-chip cache controller installed
5 hot CPU reset (low->high transition generates reset)
4 enable ATCLK stretch
3 turbo clock
=0 CLKIN is CPU clock
=1 HIGH pin selected clock (HIGH=0: CLKIN, HIGH=1: ICLK)
2-1 ICLK clock select
00 CLKIN/4 (default)
01 CLKIN/3
10 CLKIN/2
11 reserved
0 master byte swap enable (default = 0)
SeeAlso: #P058,#P060
Bitfields for OPTi 82C381/82C382 reset control:
Bit(s) Description (Table P060)
7-2 reserved
1 RESET3 control
=1 generate RESET3 on RESET2 only after a HLT instruction
=0 generate RESET3 immediately on RESET2 (default)
0 activate cache controller FLUSH# pin (default = 1)
SeeAlso: #P058,#P059,#P061
Bitfields for OPTi 82C381/82C382 remapping address:
Bit(s) Description (Table P061)
7-5 reserved
4 enable remapping
3-0 remap address range
!!!opti\82c381.pdf p.32
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 shadow RAM control:
Bit(s) Description (Table P062)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 memory enable:
Bit(s) Description (Table P063)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 memory bank configuration:
Bit(s) Description (Table P064)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 DRAM configuration:
Bit(s) Description (Table P065)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 video adapter shadow:
Bit(s) Description (Table P066)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 fast GateA20 control:
Bit(s) Description (Table P067)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 cache configuration:
Bit(s) Description (Table P068)
7 !!!
SeeAlso: #P058
Bitfields for OPTi 82C381/82C382 non-cacheable block size:
Bit(s) Description (Table P069)
7-5 block size
000 64K
001 128K
010 256K
011 512K
100 1M
101 4M (block 1 only)
101 reserved (block 2 only)
110 8M (block 1 only)
110 reserved (block 2 only)
111 disabled (default)
4-0 reserved (0)
SeeAlso: #P058,#P068,#P070
Bitfields for OPTi 82C381/82C382 non-cacheable block address:
Bit(s) Description (Table P070)
7-0 bits 23-16 of non-cacheable block's address
Note: the selected address must be a multiple of the block size
selected by register 18h/1Ah
SeeAlso: #P058,#P069,#P071
Bitfields for OPTi 82C381/82C382 cacheable area:
Bit(s) Description (Table P071)
7-4 cacheable address range
0000 16M
0001 1M
0010 2M
0011 3M
...
1111 15M
3 256K remapped area is cacheable
2-0 reserved
SeeAlso: #P058
----------P00220024--------------------------
PORT 0022-0024 - OPTi 82C463MV CHIPSET - CONFIGURATION REGISTERS
Note: every access to PORT 0024h must be preceded by a write to PORT 0022h,
even if the same register is being accessed a second time
SeeAlso: PORT 0022h"82C206"
0022 ?W index for accesses to data port (see #P072)
0024 RW chip set data
(Table P072)
Values for OPTi 82C463MV configuration register index:
30h
31h
32h
33h
34h
35h
36h
37h
38h non-cacheable block 1 size (see #P)
39h non-cacheable block 1 address (see #P)
3Ah non-cacheable block 2 size (see #P)
3Bh non-cacheable block 2 address (see #P)
3Ch-3Fh reserved
40h SMI control
41h doze control
42h timer control
43h LCD monitor
44h LCD timer
45h disk timer
46h keyboard timer
47h general timer
48h GNR_ACCESS I/O base address
49h GNR_ACCESS control
4Ah CSG0# base address
4Bh CSG0# control
4Ch CSG1# base address
4Dh CSG1# control
4Eh idle timer control
4Fh idle timer
50h suspend/resume control
51h beeper/sequencer control
52h general-purpose register 1
53h general-purpose register 2
54h PPWR control 1
55h PPWR control 2
56h PIO control 1
57h PIO control 2
58h low-battery configuration
59h resume control 2
5Ah timer configuration
5Bh PMI enable
5Ch SMI source (low)
5Dh SMI source (high)
5Eh clock stretching control
5Fh resume interrupt control
60h software sequencer address
61h CPU clock control
62h doze mode IRQ selects
63h idel timer IRQ selects
64h PMI IRQ selects
65h doze-mode configuration
66h suspend control
67h CPU frequency
68h timer clock source
69h R_TIMER
6Ah resume IRQ selects
6Bh resume sources
6Ch-6Fh TMP0 - TMP3
----------P00220024--------------------------
PORT 0022-0024 - OPTi "Viper" (82C557) CHIPSET - SYSTEM CONTROL REGISTERS
Note: every access to PORT 0024h must be preceded by a write to PORT 0022h,
even if the same register is being accessed a second time
SeeAlso: PORT 0022h"82C206"
0022 ?W index for accesses to data port (see #P073)
0023 RW DMA clock select (see #P046)
0024 RW chip set data
(Table P073)
Values for OPTi "Viper" (82C557) system control registers:
00h Byte Merge/Prefetch and Sony Cache Module control
!!!
19h Memory Decode Control register 3
----------P00220025--------------------------
PORT 0022-0025 - INTEL 82360SL CHIPSET (FOR 386SL)
0022 -W CPU write mode register
0023 R- configuration status register
bit 7: 82360 configuration is open
0024 -W 82360 configuration index
0025 RW 82360 configuration data
Bitfields for Intel 82360SL CPU write mode register:
Bit(s) Description (Table P074)
0 unlock configuration space
1 enable selected unit
3-2 unit
00 memory configuration
01 cache
10 internal bus
11 external bus
----------P0022002B--------------------------
PORT 0022-002B - INTEL 82355, PART OF CHIPSET FOR 386sx
Note: initialisation in POST will disable these addresses, only a hard
reset will enable them again.
0022w RW 82335 MCR memory configuration register (if LOCK=0) (see #P075)
0024w RW 82335 RC1 roll compare register (if LOCK=0) (see #P076)
0026w RW 82335 RC2 roll compare register (if LOCK=0) (see #P076)
0028w RW 82335 CC0 address range compare register (if LOCK=0) (see #P077)
002Aw RW 82335 CC1 address range compare register (if LOCK=0) (see #P077)
Bitfields for 82335 MCR memory configuration register:
Bit(s) Description (Table P075)
15-12 reserved
11 "VRO" video read only (0=r/w, 1=r/o)
10 "EN#"
0=enable video RAM accesses (A0000h-8FFFFh)
1=disable accesses
9 "ENADP#"
0=enable adapter ROM accesses (C0000h-8FFFFh)
1=disable adapter ROM accesses, shadow enabled
8 "ROMSIZE" 0=256KB ROM, 1=512KB ROM
7-6 "INTERL" memory interleaving
00 = 1 memory bank installed (no interleave)
01 = 2 memory banks installed
10 = 3 memory banks installed
11 = 4 memory banks installed
5 reserved
4 "DSIZE" 0=1MBx1DRAMs, 1=256KBx1 or 256KBx4 DRAMs
3 "S640" base memory size is 0=512KB, 1=640KB
2-1 reserved
0 "ROMEN#" ROM enable
0 enable BIOS ROM accesses (E0000h-FFFFFh)
1 disable BIOS ROM accesses, enable shadow
Note: One of the remaining reserved bits is the LOCK bit, which will be set
during power on, disabling access to the 82335s registers.
Bitfields for 82335 roll compare register:
Bit(s) Description (Table P076)
15-9 selects address range to be remapped (C23-C17)
8 reserved
7-1 selects address bits to be included in re-mapping comparision (M23-M17)
0 "EN" enables roll address mapping
Bitfields for 82335 address range compare register:
Bit(s) Description (Table P077)
15-11 specifies top of address range (C23-C19)
10-8 reserved
7-3 selects address bits to be included in address range comparision
(M23-M19)
2-1 reserved
0 "EN" enable address range comparision
----------P00240028--------------------------
PORT 0024-0028 - HEADLAND HTK340 SHASTA 386/486 CHIPSET
0024 Rw data port
0028 ?W index port to chipset registers (see #P078,#P079)
(Table P078)
Values for Headland HT321 register index:
00h R chip/revision,read-only
bit7-4: reserved (=0)
bit3-0: chip revision, 0=A, 1=B, 3=D
01h RW system clocking (default=00h)
bit7-4: reserved (=0)
bit3-0: ISA speed set
02h RW system parameters (default=00h) (see #P080)
04h RW co-processor (default=00h)
bit7-3: reserved (=0)
bit2=1: soft-NPU reset blocked (386 only)
bit1=1: weitek installed
bit0=1: 387 installed
06h RW DMA (default=00h) (see #P081)
07h RW EPROM (default=00h) (see #P082)
08h RW I/O and memory map holes (default=00h)
bit7-4: reserved (=0)
bit3 : 0/1 I/O map hole-A
bit2 : reserved (=0)
bit1 : 0/1 memory map hole-B
bit0 : reserved (=0)
10h RW hole-A low address (default=00h)
11h RW hole-A high address (default=00h)
19h RW mem hole-B start address, lower (default=00h)
1Ah RW mem hole-B start address, higher (default=00h)
bit7-6: reserved (=0)
bit5-0: address of mem hole-B start
1Ch RW mem hole-B end address, lower (default=00h)
1Dh RW mem hole-B end address, higher (default=00h)
bit7-6: reserved (=0)
bit5-0: address of mem hole-B end
SeeAlso: #P079
(Table P079)
Values for Headland HT342 register index:
20h R identifier port read
bit7-4: DRAM controller identifier (0010b)
bit3-0: revision number (0=A)
21h R feature port read (default=00h)
24h RW DRAM options port #1 (default=00h)
bit7 : 0/1 staggered refresh
bit6 : refresh type
bit5 : 0/1 DRAM paging
bit4-2: CAS interleave
bit1-0: banks
25h DRAM options port #2 (default=00h)
bit7-6: DRAM bank 1 type
bit5-4: DRAM bank 2 type
bit3-2: DRAM bank 1?? type
bit1-0: DRAM bank 0 type
26h RW DRAM options port #3 (default=FFh) (see #P083)
27h RW DRAM options port #4 (default=FFh) (see #P084)
28h RW data transfer control port (default=00h)
doubled indexed registers (28h-2Ah)
bit7 : initiate transfer
bit6 : read/write transfer
bit5-4: reserved
bit3-0: transfer/destination
29h RW RAM address register (default=00h)
doubled indexed registers (28h-2Ah)
bit7-5: reserved
bit4-0: RAM address registers contents
2Ah RW data transfer port (default=00h)
doubled indexed registers (28h-2Ah)
bit7-6: reserved
bit5 : EMS translation
bit4 : reserved
bit3 : 0/1 cacheing
bit2 : 0/1 write
bit1 : 0/1 read
bit0 : 0/1 shadow
2Bh RW other options (default=00h) (see #P085)
2Dh RW DRAM options port #5 (default=03h)
bit7-5: reserved
bit4 : 0/1 10µs RAS timeout
bit3-2: BUS speed
bit1-0: BUS recovery for DRAM cycles
00b=0: 4-1-1-1 10b=0.5
01b=1: 4-2-2-2 11b=1??
82h read transfer
C2h write transfer
SeeAlso: #P078
Bitfields for Headland HT321 register 02h (system parameters):
Bit(s) Description (Table P080)
7-6 IO recovery time (rev. D+)
5 parity override
4-3 cycle-width
2 0/1 PORT 0092h functionality
1 IO decode
0 0/1 posted backplane MEMWN cycles
SeeAlso: #P078
Bitfields for Headland HT321 register 06h (DMA control):
Bit(s) Description (Table P081)
7 reserved (=0)
6 1/0 IOCHRDY during master cycle (rev. C+)
5 0/1 fast sample DMA
4-3 DMA waitstate 00b=3 .. 11b=0
2 0/1 DMA flow-through mode
1 0/1 extended DMA page register
0 DMA clock
SeeAlso: #P078
Bitfields for Headland HT321 register 07h (EPROM control):
Bit(s) Description (Table P082)
7-6 reserved (=0)
5 0/1 EADS CACHE invalidation for EPROM writes (rev. D+)
4 0/1 ROMEN for EPROM writes (rev. C+)
3 0/1 middle BIOS region of 64KB space below 16MB
2 ROM-size (0=64KB, 1=128KB)
1 V-BIOS-add (0=separate, 1=same device)
0 ROM-access time (0=250ns, 1=125ns)
SeeAlso: #P078
Bitfields for Headland HT342 register 26h (DRAM CAS control):
Bit(s) Description (Table P083)
7 CAS hold on RAS (CAS before RAS refresh)
6 CAS precharge
5 CAS burst delay
4 CAS delay (writes)
3 CAS delay (reads)
2 CAS active time (writes)
1-0 CAS active time (reads)
SeeAlso: #P079,#P084
Bitfields for Headland HT342 register 27h (DRAM RAS control):
Bit(s) Description (Table P084)
7 RAS delay
6-5 RAS active (writes)
4-2 RAS active (reads)
1-0 RAS precharge
SeeAlso: #P079,#P083
Bitfields for Headland HT342 register 2Bh (other options):
Bit(s) Description (Table P085)
7 reserved
6 0/1 middle BIOS
5 0/1 data pipeline
4 0/1 data pipeline
3 IO-decode
2 reserved
1 16bit DMA bridge
0 0/1 write buffering
SeeAlso: #P079
----------P00260027--------------------------
PORT 0026-0027 - INTEL 82347 POWER MANAGEMENT PERIPHERAL
SeeAlso: PORT 0178h-0179h
0026 -W index for data port (see #P086)
0027 RW power management data
(Table P086)
Values for Intel 82437 Power Management Peripheral register index:
C0h suspend/wakeup status, system state
C1h power supply and activity status, general-purpose output/control
C2h control bits
C3h activity mask
C4h NMI mask
C5h I/O range for activity monitor
C6h power output control bits, ON state
C7h power output control bits, Doze state
C8h power output control bits, Sleep state
C9h power output control bits, Suspend state
CAh power control bits polarity control
CBh current output bits
CCh Doze timeout
CDh Sleep timeout
CEh Suspend timeout
CFh LCD display power timeout
D0h EL display power timeout
----------P0028002A--------------------------
PORT 0028-002A - 80486 "Deep Green" motherboard - ???
0028 ?W index for data port
002A RW ??? data port
Note: in order to access to the registers available through PORT 002A,
an unlocking sequence must be written via PORT 0028: write
A0h, 05h, index to PORT 0028, then read/write PORT 002A, then
write A5h to PORT 0028
----------P002E002F--------------------------
PORT 002E-002F - DELL ENHANCED PARALLEL PORT
SeeAlso: PORT 015Ch,PORT 026Eh,PORT 0398h
002E -W index for data port (see #P087)
002F RW EPP command data
(Table P087)
Values for Dell Enhanced Parallel Port register index:
00h bit 0: ???
02h bit 7: port in bidirectional mode
04h bits 0 and 2: ECP/EPP mode control
----------P002E002F--------------------------
PORT 002E-002F - Intel "Nonolet" Motherboard - POWER MANAGEMENT
002E ?W index for data port
002F ?W data port
code sequence posted in fido7.nice.sources by Konstantin Mohorea:
out 2Eh,0Ch
out 2Fh,75h
out 2Eh,11h
out 2Fh,00h
out 2Eh,0Dh
out 2Fh,A0h
----------P0038003F--------------------------
PORT 0038-003F - PC radio by CoZet Info Systems
Notes: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
All of these addresses show a readout of FF in initial state.
Once started, all of the addresses show FB, whatever might happen.
----------P0040005F--------------------------
PORT 0040-005F - PIT - PROGRAMMABLE INTERVAL TIMER (8253, 8254)
Note: XT & AT use ports 40h-43h; PS/2 uses ports 40h, 42h-44h, and 47h
SeeAlso: PORT 0044h,PORT 0048h
0040 RW PIT counter 0, counter divisor (XT, AT, PS/2)
0041 RW PIT counter 1, RAM refresh counter (XT, AT)
don't set below 3 on PCs (default 12h)
0042 RW PIT counter 2, cassette & speaker (XT, AT, PS/2)
During normal operation mode (8253) 40h-42h set the counter values on
write and get the current counter value on read. In 16bit modes two
consequtive writes/reads must be issued, first with the low byte,
followed by the high byte. In 8254 read back modes, all selected
counters and status are latched and must be read out completely
before normal operation is valid again. Each counter switches back
to normal operation after read out. In 'get status and counter'
mode the first byte read is the status, followed by one or two
counter values. (see #P088)
0043 RW PIT mode port, control word register for counters 0-2 (see #P089)
Once a control word has been written (43h), it must be followed
immediately by performing the corresponding action to the counter
registers (40h-42h), else the system may hang!!
Bitfields for 8254 PIT counter status byte:
Bit(s) Description (Table P088)
7 PIN status of OUTx Pins (1=high, 0=low)
6 counter start value loaded
=0: yes, so counter latch is valid to be read
=1: no, wait for counter latch to be set (may last a while)
5-0 counter mode, same as bit5-0 at 43h
SeeAlso: #P089
Bitfields for 8253/8254 PIT mode control word:
Bit(s) Description (Table P089)
7-6 counter select
00 counter 0 select
01 counter 1 select (not PS/2)
10 counter 2 select
11 (8253) reserved
(8254) read back counter (see #P088)
---if counter select---
5-4 counter access
00 counter latch command
BUG: Intel Neptune/Mercury/Aries Chipset 8237IB (SIO) needs
a short delay after issuing this command, else the
MSB may be outdated concerning the LSB, resulting
in large measuring errors.
Workaround: Check for this condition by comparing
results with last results and don't use erroneous
results.
01 read/write counter bits 0-7 only
10 read/write counter bits 8-15 only
11 read/write counter bits 0-7 first, then 8-15
3-1 counter mode
000 mode 0 select - zero detection interrupt
001 mode 1 select - programmable one shot
x10 mode 2 select - rate generator
x11 mode 3 select - square wave generator
counts down twice by two at a time; latch status and check
value of OUT pin to determine which half-cycle is active
divisor factor 3 not allowed!
100 mode 4 select - software triggered strobe
101 mode 5 select - hardware triggered strobe
0 counting style
0 binary counter 16 bits
1 BCD counter (4 decades)
---if read back---
5-4 what to read
00 counter status, then value
01 counter value
10 counter status
11 reserved
3 select counter 2
2 select counter 1
1 select counter 0
0 reserved (0)
Note: after issuing a read back 'get status' command, any new read back
command is ignored until the status is read from all selected
counters.
----------P00440047--------------------------
PORT 0044-0047 - Microchannel - PROGRAMMABLE INTERVAL TIMER 2
SeeAlso: PORT 0040h,PORT 0048h
0044 RW PIT counter 3 (PS/2)
used as fail-safe timer. generates an NMI on time out.
for user generated NMI see at 0462.
0047 -W PIT control word register counter 3 (PS/2, EISA)
bit 7-6 = 00 counter 3 select
= 01 reserved
= 10 reserved
= 11 reserved
bit 5-4 = 00 counter latch command counter 3
= 01 read/write counter bits 0-7 only
= 1x reserved
bit 3-0 = 00
----------P0048004B--------------------------
PORT 0048-004B - EISA - PROGRAMMABLE INTERVAL TIMER 2
Note: this second timer is also supported by many Intel chipsets
SeeAlso: PORT 0040h,PORT 0044h
0048 RW EISA PIT2 counter 3 (Watchdog Timer)
0049 ?? EISA 8254 timer 2, not used (counter 4)
004A RW EISA PIT2 counter 5 (CPU speed control)
004B -W EISA PIT2 control word
--------K-P0060006F--------------------------
PORT 0060-006F - KEYBOARD CONTROLLER 804x (8041, 8042) (or PPI (8255) on PC,XT)
Note: XT uses ports 60h-63h, AT uses ports 60h-64h
0060 RW KB controller data port or keyboard input buffer (ISA, EISA)
should only be read from after status port bit0 = 1
should only be written to if status port bit1 = 0
0060 R- KeyBoard or KB controller data output buffer (via PPI on XT)
PC: input from port A of 8255, if bit7 in 61h set (see #P105)
get scancodes, special codes (in PC: with bit7 in 61h cleared)
(see #P099)
0061 R- KB controller port B control register (ISA, EISA)
system control port for compatibility with 8255 (see #P102)
0061 -W KB controller port B (ISA, EISA) (PS/2 port A is at 0092)
system control port for compatibility with 8255 (see #P101)
0061 -W PPI Programmable Peripheral Interface 8255 (XT only)
system control port (see #P103)
0062 RW PPI (XT only) data port C (see #P104)
0063 RW PPI (XT only) command mode register (see #P106)
0064 R- keyboard controller read status (see #P107,#P108,#P109)
0064 -W keyboard controller input buffer (ISA, EISA) (see #P110)
0064 -W (Amstrad/Schneider PC1512) set 'DIP switch S1' setting
stored in CMOS RAM that PPI should report for compatibility
0065 -W (Amstrad/Schneider PC1512) set 'DIP switch S2' RAM size setting
stored in CMOS RAM, that PPI port C (PORT 0064h) should report for
compatibility
0065 R- communications port (Olivetti M24)
Bitfields for AT keyboard controller input port:
Bit(s) Description (Table P090)
7 keyboard enabled
6 =0 CGA, else MDA
5 =0 manufacturing jumper installed
4 =0 system RAM 512K, else 640K
3-0 reserved
SeeAlso: #P091,#P093
Bitfields for AT keyboard controller input port (Compaq):
Bit(s) Description (Table P091)
7 security lock is unlocked
6 =0 Compaq dual-scan display, 1=non-Compaq display
5 system board dip switch 5 is OFF
4 =0 auto speed selected, 1=high speed selected
3 =0 slow (4MHz), 1 = fast (8MHz)
2 no math coprocessor installed
1-0 reserved
SeeAlso: #P092
Bitfields for AT keyboard controller output port:
Bit(s) Description (Table P092)
7 keyboard data output
6 keyboard clock output
5 input buffer NOT full
4 output buffer NOT empty
3 reserved (see note)
2 reserved (see note)
1 gate A20
0 system reset
Note: bits 2 and 3 are the turbo speed switch or password lock on
Award/AMI/Phoenix BIOSes. These bits make use of nonstandard
keyboard controller BIOS functionality to manipulate
pin 23 (8041 port 22) as turbo switch for AWARD
pin 35 (8041 port 15) as turbo switch/pw lock for Phoenix
SeeAlso: #P090,#P093
Bitfields for HP Vectra keyboard controller output port:
Bit(s) Description (Table P093)
7-5 reserved
4 output buffer full (OBF) interrupt
3 HP SVC interrupt
2 HP-HIL controller AutoPoll
1 A20 gate
0 system reset
SeeAlso: #P092,#P094
Bitfields for HP Vectra command byte:
Bit(s) Description (Table P094)
7 reserved (0)
6 scancode conversion mode (1 = PC/XT, 0 = PC/AT)
5 unused
4 disable keyboard (unless bit 3 set)
3 override keyboard disable
2 System Flag (may be read from PORT 0060h)
1 reserved
0 OBF interrupt enable
SeeAlso: #P093
(Table P095)
Values for keyboard commands (data also goes to PORT 0060h):
Value Count Description
EDh double set/reset mode indicators Caps Num Scrl
bit 2 = CapsLk, bit 1 = NumLk, bit 0 = ScrlLk
all other bits must be zero.
EEh sngl diagnostic echo. returns EEh.
EFh sngl NOP (No OPeration). reserved for future use
EF+26h double [Cherry MF2 G80-1501HAD] read 256 bytes of chipcard data
keyboard must be disabled before this and has to
be enabled after finished.
F0h double get/set scan code set
00h get current set
01h scancode set 1 (PCs and PS/2 mod 30, except Type 2 ctrlr)
02h scancode set 2 (ATs, PS/2, default)
03h scancode set 3
F2h sngl read keyboard ID (read two ID bytes)
AT keyboards returns FA (ACK)
MF2 returns AB 41 (translation) or
AB 83 (pass through)
F3h double set typematic rate/delay
format of the second byte:
bit7=0 : reserved
bit6-5 : typemativ delay
00b=250ms 10b= 750ms
01b=500ms 11b=1000ms
bit4-0 : typematic rate (see #P100)
F4h sngl enable keyboard
F5h sngl disable keyboard. set default parameters (no keyboard scanning)
F6h sngl set default parameters
F7h sngl [MCA] set all keys to typematic (scancode set 3)
F8h sngl [MCA] set all keys to make/release
F9h sngl [MCA] set all keys to make only
FAh sngl [MCA] set all keys to typematic/make/release
FBh sngl [MCA] set al keys to typematic
FCh double [MCA] set specific key to make/release
FDh double [MCA] set specific key to make only
FEh sngl resend last scancode
FFh sngl perform internal power-on reset function
Note: each command is acknowledged by FAh (ACK), if not mentioned otherwise.
See PORT 0060h-R for details.
SeeAlso: #P096
(Table P096)
Values for Mouse functions (for PS/2-like pointing devices):
Value Count Description
E6h sngl set mouse scaling to 1:1
E7h sngl set mouse scaling to 2:1
E8h double set mouse resolution
(00h=1/mm, 01h=2/mm, 02h=4/mm, 03h=8/mm)
E9h sngl get mouse information
read two status bytes:
byte 0: flags (see #P097)
byte 1: resolution
EAh sngl set mouse to stream mode (mouse sends data on any changes)
EBh sngl get mouse data (from mouse to controller) (see #P098)
on reading, each data packet consists of 8 bytes:
ECh sngl reset mouse wrap mode (to normal mode)
EEh sngl set wrap mode
F0h sngl set remote mode (instead of stream mode), mouse sends data
only on issueing command EBh.
F2h sngl read mouse ID (read one, two?? ID bytes)
00h=mouse
F3h double set mouse sample rate in reports per second
0Ah=10/s 50h= 80/s
14h=20/s 64h=100/s
28h=40/s C8h=200/s
3Ch=60/s
F4h sngl enable mouse (in stream mode)
F5h sngl disable mouse (in steam mode), set default parameters
F6h sngl reset to defaults: 100/s, scaling 1:1, stream-mode, 4/mm,
disabled
FEh sngl resend last mouse data (8 bytes, see EBh)
FFh sngl reset mouse
Notes: must issue command D4h to PORT 0064h first to access mouse functions
all commands except ECh and FFh are acknowledged by FAh (ACK) or
FEh (Resend); get mouse ID (F2h) returns mouse ID.
SeeAlso: #P095
Bitfields for mouse status byte 0:
Bit(s) Description (Table P097)
7 unused
6 remote rather than stream mode
5 mouse enabled
4 scaling set to 2:1
3 unused
2 left button pressed
1 unused
0 right button pressed
SeeAlso: #P096,#P098
Format of mouse data packet:
Offset Size Description (Table P098)
00h BYTE status
bit7 : y-data overrun
bit6 : x-data overrun
bit5 : y-data negative
bit4 : x-data negative
bit3-2=0: reserved
bit1 : right button pressed
bit0 : left button pressed
01h BYTE reserved
02h BYTE x-data
03h BYTE reserved
04h BYTE y-data
05h BYTE reserved
06h BYTE z-data (0)
07h BYTE reserved
SeeAlso: #P096,#P097
(Table P099)
Values for keyboard special codes:
00h (MF2 in codeset2&3 or AT keyboards) keydetection/overrun error
00h (mouse) ID
AAh BAT completion code (sent after errorfree Basic Assurance Test)
ABh first byte of general MF2 keyboard ID
EEh Echo command return
FAh Acknowledge (all general commands except Resend and Echo)
FAh (mouse) Acknowledge (all commands except commands ECh,F2h,FFh)
FCh (MF2) BAT Failure Code (error in second half of the power on self test)
FDh (AT-keyboard) BAT Failure Code (error in the second half of the
power-on self test)
FEh Resend: CPU to controller should resend last keyboard-command
FEh (mouse) CPU to controller should resend last mouse-command
FFh (MF2 in codeset1) keydetection/overrun error
Note: keyboard stops scanning and waits for next command after returning
code FCh or FDh
SeeAlso: PORT 0060h-R
(Table P100)
Values for keyboard typematic rate:
00000b=30.0 10000b=7.5
00001b=26.7 10001b=6.7
00010b=24.0 10010b=6.0
00011b=21.8 10011b=5.5
00100b=20.0 10100b=5.0
00101b=18.5 10101b=4.6
00110b=17.1 10110b=4.3
00111b=16.0 10111b=4.0
01000b=15.0 11000b=3.7
01001b=13.3 11001b=3.3
01010b=12.0 11010b=3.0
01011b=10.9 11011b=2.7
01100b=10.0 11100b=2.5
01101b= 9.2 11101b=2.3
01110b= 8.5 11110b=2.1
01111b= 8.0 11111b=2.0
SeeAlso: #P095
Bitfields for KB controller port B (system control port) [output]:
Bit(s) Description (Table P101)
7 pulse to 1 for IRQ1 reset (PC,XT)
6-4 reserved
3 I/O channel parity check disable
2 RAM parity check disable
1 speaker data enable
0 timer 2 gate to speaker enable
SeeAlso: PORT 0061h-W,#P102
Bitfields for KB controller port B control register (system control port) [input]:
Bit(s) Description (Table P102)
7 RAM parity error occurred
6 I/O channel parity error occurred
5 mirrors timer 2 output condition
4 toggles with each refresh request
3 NMI I/O channel check status
2 NMI parity check status
1 speaker data status
0 timer 2 clock gate to speaker status
SeeAlso: PORT 0061h-R,#P101
Bitfields for Progr. Peripheral Interface (8255) system control port [output]:
Bit(s) Description (Table P103)
7 clear keyboard (only pulse, normally kept at 0)
6 =0 hold keyboard clock low
5 NMI I/O parity check disable
4 NMI RAM parity check disable
3 =0 read low nybble of switches S2
=1 read high nybble of switches S2
2 reserved, often used as turbo switch
original PC: cassette motor off
1 speaker data enable
0 timer 2 gate to speaker enable
Note: bits 2 and 3 are sometimes used as turbo switch
SeeAlso: PORT 0061h-W,#P0051,#P104,#P105,#P106
Bitfields for PPI (XT only) data port C:
Bit(s) Description (Table P104)
7 RAM parity error occurred
6 I/O channel parity error occurred
5 timer 2 channel out
4 reserved
original PC: cassette data input
---
3 system board RAM size type 1
2 system board RAM size type 2
1 coprocessor installed
0 loop in POST
---
3-0 DIL switch S2 high/low nybble (depending on PORT 0061h bit 3)
SeeAlso: PORT 0062h-RW,#P103,#P105,#P106
Bitfields for PPI (PC,XT only) equipment switches [input]:
Bit(s) Description (Table P105)
7-6 number of disk drives
00 1 diskette drive
01 2 diskette drives
10 3 diskette drives
11 4 diskette drives
5-4 initial video
00 reserved (video adapter has on-board BIOS)
01 40*25 color (mono mode)
10 80*25 color (mono mode)
11 MDA 80*25
3-2 memory size (using 256K chips)
00 256K
01 512K
10 576K
11 640K
3-2 memory size (using 64K chips)
00 64K
01 128K
10 192K
11 256K
3-2 memory size (original PC)
00 16K
01 32K
10 48K
11 64K
1-0 reserved
1 NPU (math coprocessor) present
0 boot from floppy
SeeAlso: #P104,#P106,PORT 0060h-R
Bitfields for PPI (8255) command mode register:
Bit(s) Description (Table P106)
7 activation function (0 = bit set/reset, 1 = mode set function)
6,5 port A mode: 00 = mode0, 01 = mode1, 1x = mode2
4 port A direction: 0 = output, 1 = input
3 port C bits 7-4 direction: 0 = output, 1 = input
2 port B mode: 0 = mode0, 1 = mode1
1 port B direction: 0 = output, 1 = input
0 port C bits 3-0 direction: 0 = output, 1 = input
Note: Attention: Never write anything other than 99h to this port
(better: never write anything to this port, only during BIOS
init), as other values may connect multiple output drivers
and will cause hardware damage in PC/XTs! By setting command
word to 99h, PPI will be set in input/output modes as it is
necessary to support the commonly known IO-ports 60, 61, 62
as desired.
SeeAlso: #P103,#P104,#P105
Bitfields for keyboard controller read status (ISA, EISA):
Bit(s) Description (Table P107)
7 parity error on transmission from keyboard
6 receive timeout
5 transmit timeout
4 keyboard interface inhibited by keyboard lock
3 =1 data written to input register is command (PORT 0064h)
=0 data written to input register is data (PORT 0060h)
2 system flag status: 0=power up or reset 1=selftest OK
1 input buffer full (input 60/64 has data for 8042)
no write access allowed until bit clears
0 output buffer full (output 60 has data for system)
bit is cleared after read access
SeeAlso: PORT 0064h-R,#P108,#P109,#P110
Bitfields for keyboard controller read status (MCA):
Bit(s) Description (Table P108)
7 parity error on transmission from keyboard
6 general timeout
5 mouse output buffer full
4 keyboard interface inhibited by keyboard lock
3 =1 data written to input register is command (PORT 0064h)
=0 data written to input register is data (PORT 0060h)
2 system flag status: 0=power up or reset 1=selftest OK
1 input buffer full (60/64 has data for 804x)
no write access allowed until bit clears
0 output buffer full (output 60 has data for system)
bit is cleared after read access
SeeAlso: #P107,#P109,#P110
Bitfields for keyboard controller read status (Compaq):
Bit(s) Description (Table P109)
7 parity error detected (11-bit format only). If an
error is detected, a Resend command is sent to the
keyboard once only, as an attempt to recover.
6 receive timeout. transmission didn't finish in 2mS.
5 transmission timeout error
bit 5,6,7 cause
1 0 0 No clock
1 1 0 Clock OK, no response
1 0 1 Clock OK, parity error
4 =0 security lock engaged
3 =1 data in OUTPUT register is command
=0 data in OUTPUT register is data
2 system flag status: 0=power up or reset 1=soft reset
1 input buffer full (60/64 has data for 804x)
no write access allowed until bit clears
0 output buffer full (PORT 0060h has data for system)
bit is cleared after read access
SeeAlso: #P107,#P108,#P110
(Table P110)
Values for keyboard controller commands (data goes to PORT 0060h):
Value Description
20h read read byte zero of internal RAM, this is the last KB command
sent to the 8041/8042
Compaq put current command byte on PORT 0060h (see #P111,#P112)
21-3F read reads the byte specified in the lower 5 bits of the command
in the 804x's internal RAM (see #P115)
60-7F double writes the data byte to the address specified in the 5 lower
bits of the command
60h Compaq Load new command (60 to [64], command to [60]) (see #P112)
(also general AT-class machines)
A0h AMI get ASCIZ copyright message on PORT 0060h
A1h AMI get controller version byte on PORT 0060h
A1h Compaq unknown speedfunction ??
A2h Compaq unknown speedfunction ??
A2h AMI set keyboard controller pins 22 and 23 low
A3h Compaq Enable system speed control
A3h AMI set keyboard controller pins 22 and 23 high
A4h MCA check if password installed
returns PORT 0060h code F1h if no password, FAh if installed
A4h Compaq Toggle speed
A4h AMI set internal system speed flag to low
A5h MCA load password
write successive scan codes to PORT 0060h, terminate with 00h
A5h AMI set internal system speed flag to high
A5h Compaq Special read. the 8042 places the real values of port 2
except for bits 4 and 5 wich are given a new definition in
the output buffer. No output buffer full is generated.
if bit 5 = 0, a 9-bit keyboard is in use
if bit 5 = 1, an 11-bit keyboard is in use
if bit 4 = 0, output-buff-full interrupt disabled
if bit 4 = 1, output-buffer-full interrupt enabled
A6h MCA check password
A6h AMI get internal system speed flag on PORT 0060h
A6h Compaq unknown speedfunction ??
A7h MCA disable mouse port
A7h AMI set internal flag indicating bad write cache
A8h MCA enable mouse port
A8h AMI set internal flag indicating good write cache
A9h MCA test mouse port, return test result on PORT 0060h (see #P114)
A9h AMI get internal flag indicating cache OK to PORT 0060h
AAh sngl initiate self-test. will return 55h to data port if self-test
successful, FCh if failed
AAh Compaq initializes ports 1 and 2, disables the keyboard and clears
the buffer pointers. It then places 55h in the output buffer.
ABh sngl initiate interface test, return result value on PORT 0060h
(see #P114)
ACh read diagnostic dump. the contents of the 804x RAM, output port,
input port, status word are sent to PORT 0060h
ADh sngl disable keyboard (sets bit 4 of commmand byte)
ADh Vectra HP Vectra diagnostic dump
AEh sngl enable keyboard (resets bit 4 of commmand byte)
AFh AWARD Enhanced Command: read keyboard version
AFh AMI set extended controller RAM
write address to PORT 0060h, wait for controller ready, then
write value to PORT 0060h
B1h AMI set keyboard controller P11 line low
B2h AMI set keyboard controller P12 line low
B3h AMI set keyboard controller P13 line low
B4h AMI set keyboard controller P22 line low
B5h AMI set keyboard controller P23 line low
B8h AMI set keyboard controller P10 line high
B9h AMI set keyboard controller P11 line high
BAh AMI set keyboard controller P12 line high
BBh AMI set keyboard controller P13 line high
BCh AMI set keyboard controller P22 line high
BDh AMI set keyboard controller P23 line high
C0h read read input port and place on PORT 0060h
bit 7 keyboard NOT locked
bit 6 =0 first video is CGA
=1 first video is MDA
bit 5 =0 factory testmode
=1 normal
bit 4 =0 256KB RAM, 1=512KB
bit 5,3-0 are used in Intel chipset 386sx machines with
AMI/Phoenix BIOSes for BIOS specific hardware settings
bit 2 (MCA) no keyboard power
bit 1 (MCA) current mouse serial data input state
bit 0 (MCA) current keyboard serial input state
C0h Compaq places status of input port in output buffer. Use this
command only when the output buffer is empty
C1h MCA Enhanced Command: poll input port Low nibble, continuously
place in PORT 0064h bits 7-4 until next command
C2h MCA Enhanced Command: poll input port High nibble, continuously
place in PORT 0064h bits 7-4 until next command
C8h AMI unblock keyboard controller lines P22 and P23
C9h AMI block keyboard controller lines P22 and P23
CAh AMI read keyboard mode, return in 0060 bit 0
(bit clear if ISA mode, set if PS/2 mode)
CBh AMI set keyboard mode (write back mode byte returned by CAh,
modifying only bit 0)
CCh AMI ??? (used by AMI BIOS v1.00.12.AX1T APM code)
D0h read read output port and place on PORT 0060h (see #P113)
D0h Compaq places byte in output port in output buffer. Use this command
only when the output buffer is empty
D1h double write output port. The next byte written to PORT 0060h will
be written to the 804x output port; the original IBM AT and
many compatibles use bit 1 of the output port to control
the A20 gate.
Important: bit 0 (system reset) should always be set here, as
the system may hang constantly, use pulse output port
(FEh) instead.
D1h Compaq the system speed bits are not set by this command use
commands A1-A6 (!) for speed functions.
D2h MCA Enhanced Command: write keyboard output buffer
D3h MCA Enhanced Command: write pointing device out.buf.
D4h MCA write to mouse/pointing device instead of to keyboard; this
controller command must precede every PORT 0060h command
directed to the mouse, otherwise it will be sent to the
keyboard
D4h AWARD Enhanced Command: write to auxiliary device
DDh sngl disable address line A20 (HP Vectra only???)
default in Real Mode
DFh sngl enable address line A20 (HP Vectra only???)
E0h read read test inputs, and place in PORT 0060h
bit0 = kbd clock, bit1 = kbd data
Exxx AWARD Enhanced Command: active output port
EDh double this is a two part command to control the state of the
NumLock, CpasLock and ScrollLock LEDs
The second byte contains the state to set LEDs.
bit 7-3 reserved. should be set to 0.
bit 2 = 0 Caps Lock LED off
bit 1 = 0 Num Lock LED off
bit 0 = 0 Scroll Lock LED off
F0-FF sngl pulse output port low for 6 microseconds.
bits 0-3 contain the mask for the bits to be pulsed. A bit is
pulsed if its mask bit is zero
bit0=system reset. Don't set to zero. Pulse only!
Note: keyboard controllers are widely different from each other. You
cannot generally exchange them between different machines.
(Award) Derived from Award's Enhanced KB controller advertising sheet.
(Compaq) Derived from the Compaq Deskpro 386 Tech. Ref. Guide.
Bitfields for Compaq keyboard command byte:
Bit(s) Description (Table P111)
7 reserved
6 =1 convert KB codes to 8086 scan codes
5 =0 use 11-bit codes, 1=use 8086 codes
4 =0 enable keyboard, 1=disable keyboard
3 ignore security lock state
2 this bit goes into bit2 status reg.
1 reserved (0)
0 generate interrupt (IRQ1) when output buffer full
SeeAlso: #P112
Bitfields for keyboard command byte (alternate description):
Bit(s) Description (Table P112)
7 reserved (0)
6 IBM PC compatibility mode
5 IBM PC mode
no parity, no stop bits, no translation
(PS/2) force mouse clock low
4 disable keyboard (clock)
3 (AT) inhibit override -- ignore keyboard lock switch
(PS/2) reserved
2 system flag
1 (AT) reserved (0)
(PS/2) enable mouse output buffer full interrupt (IRQ12)
0 enable output buffer full interrupt (IRQ1)
SeeAlso: #P111,#P113
Bitfields for keyboard controller output port:
Bit(s) Description (Table P113)
7 keyboard data (output)
6 keyboard clock (output)
5 (AT) =0 input buffer empty
(MCA) outptu buffer full with mouse byte (connected to IRQ12)
4 output buffer full with keyboard byte (connected to IRQ1)
3 (MCA) mouse data (output)
2 (MCA) mouse clock (output)
used by Intel 386sx Chipset with AMI/Phoenix BIOSes for BIOS-specific
configuration of turbo switch
1 gate address A20
0 system reset
Note: bit 0 (system reset) should always be set when writing the output
port, as the system may hang constantly; use pulse output port
(command FEh) instead.
SeeAlso: #P112
(Table P114)
Values for keyboard/mouse test result on PORT 0060h:
00h no error
01h keyboard clock line stuck low
02h keyboard clock line stuck high
03h keyboard data line is stuck low
04h keyboard data line stuck high
05h (Compaq only) diagnostic feature
SeeAlso: #P110
(Table P115)
Values for keyboard controller RAM location:
00h command byte (see #P111,#P112)
---MCA systems---
13h security on
nonzero if password enabled
14h security off
nonzero if password matched
16h password discard scancode 1
17h password discard scancode 2
Note: make codes matching either discard scancode are ignored during password
entry
----------P0065------------------------------
PORT 0065 - AT&T 6300+ - HIGH/LOW CHIP SELECT
----------P0065------------------------------
PORT 0065 - ???
0065 RW ???
bit 2: A20 gate control (set = A20 enabled, clear = disabled)
----------P00660067--------------------------
PORT 0066-0067 - AT&T 6300+ - SYSTEM CONFIGURATION SWITCHES
----------P0066------------------------------
PORT 0066 - IBM 4717 Magnetic Stripe Reader - ???
SeeAlso: PORT 0069h"Magnetic Stripe"
----------P0068------------------------------
PORT 0068 - C&T CHIPSETS - TURBO MODE CONTROL
Note: on Micronics 386-25/386-33/486-25 motherboards, setting this port to
00h enables full speed; setting it to C0h slows the system down by
a factor corresponding to the value programmed into the EISA
interval timer 2 at ports 004Ah and 004Bh
--------K-P0068006F--------------------------
PORT 0068-006F - HP Vectra Human Interface Link
SeeAlso: PORT 0060h"KEYBOARD"
0068 -W (HP-Vectra) control buffer (HP commands) (see #P116)
0069 R- (HP-Vectra) SVC (keyboard request SerViCe port)
006A -W (HP-Vectra) Acknowledge (clear processing, done)
006C-006F HP-HIL (Human Interface Link = async. serial inputs 0-7)
(Table P116)
Values for HP Vectra control buffer command code:
00h-54h insert standard key make code into 8041 scancode buf
55h-77h insert HP key make code into 8041 scancode buffer
7Ah pass through next data byte
7Bh set RAM Switch to 0
7Ch set RAM Switch to 1 (default)
7Dh set CRT Switch to 0
7Eh set CRT Switch to 1 (default)
7Fh reserved
80h-D4h insert standard key break code into scancode buffer
D5h-F7h insert HP key break code into scancode buffer
F8h enable AutoPoll
F9h disable AutoPoll
FAh-FEh reserved
FFh keyboard overrun
----------P0069------------------------------
PORT 0069 - IBM 4717 Magnetic Stripe Reader - ???
SeeAlso: PORT 0066h"Magnetic Stripe"
----------P006B006F--------------------------
PORT 006B-006F - SSGA CONTROL REGISTERS
006B ?? RAM enable/remap
006C ?? undocumented
006D ?? undocumented
006E ?? undocumented
006F ?? undocumented
----------P0070007F--------------------------
PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK)
Note: the real-time clock may be either a discrete MC146814, MC146818, or
an emulation thereof built into the motherboard chipset
SeeAlso: PORT 00A0h"XT"
0070 -W CMOS RAM index register port (ISA, EISA)
bit 7 = 1 NMI disabled from reaching CPU
= 0 NMI enabled
bit 6-0 CMOS RAM index
(64 bytes in early systems, now usually 128 bytes)
Note: any write to PORT 0070h should be followed by an action to
PORT 0071h or the RTC wil be left in an unknown state.
0071 RW CMOS RAM data port (ISA, EISA) (see #P117)
(Table P117)
Values for Real-Time Clock register number (see also CMOS.LST):
00h-0Dh clock registers
0Eh diagnostics status byte
0Fh shutdown status byte
10h diskette drive type for A: and B:
11h reserved / IBM fixed disk / setup options
12h fixed disk drive type for drive 0 and drive 1
13h reserved / AMI Extended CMOS setup (AMI Hi-Flex BIOS)
14h equipment byte
15h LSB of system base memory in Kb
16h MSB of system base memory in Kb
17h LSB of total extended memory in Kb
18h MSB of total extended memory in Kb
19h drive C extension byte
1Ah drive D extension byte
1Bh-2Dh reserved
20h-27h commonly used for first user-configurable drive type
2Eh CMOS MSB checksum over 10-2D
2Fh CMOS LSB checksum over 10-2D
30h LSB of extended memory found above 1Mb at POST
31h MSB of extended memory found above 1Mb at POST
32h date century in BCD
33h information flags
34h-3Fh reserved
35h-3Ch commonly used for second user-configurable drive type
3Dh-3Eh word to 82335 MCR memory config register at [22] (Phoenix)
42h-4Ch AMI 1990 Hyundai super-NB368S notebook
???
54h-57h AMI 1990 Hyundai super-NB368S notebook
???
5Ch-5Dh AMI 1990 Hyundai super-NB368S notebook
???
60h-61h AMI 1990 Hyundai super-NB368S notebook
???
----------P00720075--------------------------
PORT 0072-0075 - AMD-645 Peripheral Bus Controller - EXTENDED CMOS ACCESS
SeeAlso: PORT 0070h
0072 RW CMOS memory address, region 2 (256 bytes)
0073 RW CMOS memory data, region 2
0074 RW CMOS memory address, region 3 (256 bytes)
0075 RW CMOS memory data, region 3
----------P0073------------------------------
PORT 0073 - Intel 82378IB ("Saturn"/"Neptune" chipsets) - MBOARD CONFIGURATION
SeeAlso: PORT 0075h
0073 RW ???
bit 7: ???
bit 6: disable ROM shadowing
bit 5: ??? (related to IDE controller)
bit 4: ???
bit 3: ???
----------P00740076--------------------------
PORT 0074-0076 - SECONDARY CMOS (Compaq), NVRAM (IBM) ACCESS
Note: NVRAM may be 2K, 8K, or 16K
SeeAlso: PORT 0070h-007Fh,CMOS.LST
0074 -W secondary CMOS RAM (IBM NVRAM) index, low byte
0075 -W secondary CMOS RAM (IBM NVRAM) index, high (in bits 2-0)
0076 RW secondary CMOS RAM (IBM NVRAM) data byte
----------P0075------------------------------
PORT 0075 - Intel 82378IB ("Saturn"/"Neptune" chipsets) - MBOARD CONFIGURATION
SeeAlso: PORT 0073h,PORT 0078h"82378IB"
0075 R- ???
bits 3-2: external bus speed
00 50 MHz
01 66 MHz
10 60 MHz
11 40 MHz
----------P0078------------------------------
PORT 0078 - HP-Vectra - HARD RESET: NMI ENABLE/DISABLE
0078 ?W NMI enable/disable
bit 7 = 0 disable & clear hard reset from HP-HIL controller
= 1 enable hard reset from HP-HIL controller chip
bit 6-0 reserved
----------P0078------------------------------
PORT 0078 - Intel 82378IB ("Saturn"/"Neptune" chipsets) - BIOS COUNT-DOWN TIMER
Notes: the BIOS uses this port for certain fine timings; presumably it is
independent of processor speed (it appears to decrement at 1 MHz)
the address at which this port appears may be set via the 82378's
PCI configuration space word at offset 0080h (see #0860), or the
timer may be disabled entirely
SeeAlso: PORT 0075h
0078w -W set count-down timer
0078w R- get current count (timer stops when it reaches 0000h)
----------P0078007F--------------------------
PORT 0078-007F - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Note: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
----------P007C007D--------------------------
PORT 007C-007D - HP-Vectra - PIC 3 - PROGRAMMABLE INTERRUPT CONTROLLER (8259)
Notes: cascaded to first controller.
used for keyboard and input device interface.
SeeAlso: PORT 0020h-0021h,INT 68"Vectra",INT 6E"Vectra"
007C RW HP-Vectra PIC 3 see at 0020 PIC 1
007D RW HP-Vectra PIC 3 see at 0021 PIC 1
----------P0080------------------------------
PORT 0080 - MANUFACTURING DIAGNOSTICS PORT
Note: sometimes used for a POST hex display
0080 -W Manufacturing Diagnostics port
0080 R- ???
(Table P118)
Values for AMI BIOS diagnostics codes:
00h system boot completed, control passed to INT 19 bootstrap loader
01h register test
02h video initialization; NMIs disabled
03h power-on delay complete
04h pre-keyboard-test initializations complete
05h soft-reset/power-on setting determined
06h ROM enabled
07h ROM BIOS checksum test passed
08h keyboard BAT command issued
09h keyboard controller BAT result verified
0Ah keyboard controller command code issued
0Bh keyboard controller command byte written
0Ch keyboard controller pins 23/24 blocked and unblocked
0Dh keyboard controller NOP processing in progress
0Eh CMOS RAM shutdown register read/write test passed
0Fh CMOS RAM checksum calculation complete
10h CMOS RAM initialization complete
11h CMOS RAM status register initialized
12h DMA controllers 1/2 and interrupt controllers 1/2 disabled
13h video display disabled, port B initialized
14h chipset initialization, auto memory detection
15h 8254 channel 2 test half complete
16h 8254 channel 2 test completed
17h 8254 channel 1 test completed
18h 8254 channel 0 test completed
19h memory refresh started
1Ah memory refresh line is toggling
1Bh memory refresh test completed
20h base 64K memory test started
21h address line test passed
22h parity toggle complete
23h base 64K sequential read/write test passed
24h pre-interrupt-vector-initialization configuration complete
25h interrupt vectors initialized
26h 8042 input port read
27h global data initialization complete
28h post-interrupt-vector-initialization initialization complete
29h monochrome mode set
2Ah color mode set
2Bh parity toggle on option video ROM test complete
2Ch initialization before video ROM control complete
2Dh video ROM check complete
2Eh !!!
A9h returned from E0000h adapter ROM
AAh final initializations after adapter ROM initializations complete
SeeAlso: #P119,#P120
(Table P119)
Values for AWARD (non-PnP) diagnostic code:
01h Processor Test 1
02h Processor Test 2
03h initialize chips
04h test memory refresh toggle
05h blank video, initialize keyboard
06h reserved
07h test CMOS and CMOS batter status
08h setup low memory
09h early cache initialization
0Ah interrupt vector initialization
0Bh test CMOS RAM checksum
0Ch initialize keyboard
0Dh initialize video interface
0Eh test video memory
0Fh test DMA channel 0
10h test DMA channel 1
11h test DMA page registers
12h reserved
13h reserved
14h test timer channel 2
15h test master PIC mask bits
16h test slave PIC mask bits
17h test 8259 stuck interrupt bits
18h test 8259 interrupt functionality
19h test for stuck NMI
1Ah display CPU clock
1Bh-1Eh reserved
1Fh set EISA mode
20h enable Slot 0 (system board)
21h-2Fh enable Slots 1-15
30h get base and extended memory size
31h test base and extended memory
32h test EISA memory
33h-3Bh reserved
3Ch set allow-setup flag
3Dh initialize / install mouse
3Eh initialize cache controller
3Fh reserved
41h initialize floppy controller and drives
42h initialize hard disk controller and drives
43h detect / initialize serial and parallel ports
44h reserved
45h initialize math coprocessor
46h-4Dh reserved
4Eh Manufacturing Post loop / or / display any error messages
4Fh ask for password, if enabled
50h update CMOS RAM
51h pre-boot enable of parity, NMI, cache
52h initialize option ROMs
53h initialize BIOS time from RTC
60h setup boot-sector protection
61h set boot CPU speed
62h setup NumLock
63h attempt to boot via INT 19h
B0h spurious interrupt while in protected mode
B1h unclaimed NMI
BEh chipset default initialization
BFh chipset initialization
C0h turn off chipset cache
C1h check on-board memory size
C5h early shadow-RAM enable for faster boot
C6h detect external cache size
E1h-EFh setup utility pages 1-15
FFh system booting operating system
SeeAlso: #P118,#P120
(Table P120)
Values for AWARD (Plug-and-Play) POST code:
01h-02h reserved
03h initialize EISA register (if applicable)
04h reserved
05h keyboard controller test, initialize keyboard
06h reserved
07h test CMOS and CMOS batter status
09h program Cyrix CPU configuration; OEM-specific cache initialization
0Ah initialize interrupt vectors; early power management initialization
0Bh check CMOS RAM; assign I/O and memory to PCI devices
0Ch initialize BIOS data area
0Dh early chipset setup; measure CPU speed; video initialization
0Eh display Award logo, OEM-specific sign-on messages
0Fh test DMA channel 0
10h test DMA channel 1
11h test DMA page registers
12h-13h reserved
14h test timer channel 2
15h test master PIC mask bits
16h test slave PIC mask bits
17h reserved
19h test 8259 functionality
1Ah-1Dh reserved
1Eh EISA initialization (if applicable and EISA NVRAM checksum is good)
1Fh-29h reserved
30h get base and extended memory size
31h test base and extended memory
32h program on-board serial/parallel ports, floppy controller
33h-3Bh reserved
3Ch set allow-setup flag
3Dh initialize keyboard, install PS/2 mouse if attached
3Eh try to turn on L2 cache
3Fh-40h reserved
41h initialize floppy controller, drives
42h initialize hard disk controller, drives
43h initialize serial/parallel ports (if PnP)
44h reserved
45h initialize math coprocessor
46h-4Dh reserved
4Eh display any error messages
4Fh ask for password, if required
50h update CMOS RAM
51h reserved
52h initialize expansion ROMs, PCI, PnP, shadow RAM, power management
53h if not PnP, initialize serial/parallel ports; set BIOS time
54h-5Fh reserved
60h set boot-sector protection
61h turn on L2 cache; set boot speed; final chipset/PM initialization
62h setup daylight savings time; set NumLock, typematic
63h update ESCD (PnP only) if changes; boot system via INT 19h
B0h spurious interrupt while in protected mode
B1h unclaimed NMI
BEh chipset default initialization
BFh chipset initialization
C0h turn off chipset cache, init DMA/PIC/timer/RTC with default values
C1h check on-board DRAM and cache size
C3h test first 256K DRAM, expand compressed BIOS image into DRAM
C5h early shadow-RAM enable for faster boot
FFh system is booting operating system
SeeAlso: #P119
----------P0080008F--------------------------
PORT 0080-008F - DMA PAGE REGISTERS (74612)
0080 RW extra page register (temporary storage)
0081 RW DMA channel 2 address byte 2
0082 RW DMA channel 3 address byte 2
0083 RW DMA channel 1 address byte 2
0084 RW extra page register
0085 RW extra page register
0086 RW extra page register
0087 RW DMA channel 0 address byte 2
0088 RW extra page register
0089 RW DMA channel 6 address byte 2
008A RW DMA channel 7 address byte 2
008B RW DMA channel 5 address byte 2
008C RW extra page register
008D RW extra page register
008E RW extra page register
008F RW DMA refresh page register
----------P0080009F--------------------------
PORT 0080-009F - Intel386sx CHIPSET 82231
Note: includes the DMA controller functionality on PORT 0080h to PORT 008Fh
----------P0084------------------------------
PORT 0084 - Compaq POST Diagnostic
--------X-P0084------------------------------
PORT 0084 - EISA - SYNCHRONIZE BUS CYCLE
----------P00850086--------------------------
PORT 0085-0086 - Intel "Triton" chipset - ???
SeeAlso: PORT 00EBh"Triton"
0085 ?W ???
0086 ?W ???
----------P0090009F--------------------------
PORT 0090-009F - PS/2 - POS (PROGRAMMABLE OPTION SELECT)
0090 ?? Central arbitration control port
0090 RW POST diagnostic code (most PS/2 with ISA bus)
0091 R- Card selection feedback
bit 0 set when adapter addressed and responds, cleared on read
0092 RW PS/2 system control port A (port B is at PORT 0061h) (see #P121)
0094 -W system board enable/setup register (see #P122)
0095 -- reserved
0096 -W adapter enable / setup register (see #P123)
0097 -- reserved
Bitfields for PS/2 system control port A:
Bit(s) Description (Table P121)
7-6 any bit set to 1 turns activity light on
5 unused
4 watchdog timout occurred
3 =0 RTC/CMOS security lock (on password area) unlocked
=1 CMOS locked (done by POST)
2 unused
1 A20 is active
0 =0 system reset or write
=1 pulse alternate reset pin (high-speed alternate CPU reset)
Note: once set, bit 3 may only be cleared by a power-on reset
SeeAlso: #P122,#P123,MSR 00001000h
Bitfields for PS/2 system board enable/setup register:
Bit(s) Description (Table P122)
7 =1 enable functions
=0 setup functions
5 =1 enables VGA
=0 setup VGA
2 =1 enable integrated SCSI (PS/2 M77)
=0 setup integrated SCSI
SeeAlso: #P121,#P123
Bitfields for PS/2 adapter enable/setup register:
Bit(s) Description (Table P123)
7 activate Channel Reset on all slots
6-4 unused (1)
3 =1 setup adapter specified by bits 2-0
=0 enable registers
2-0 adapter slot select (000 = slot 1 ... 111 = slot 8)
SeeAlso: #P122
----------P00A000AF--------------------------
PORT 00A0-00AF - PIC 2 - PROGRAMMABLE INTERRUPT CONTROLLER (8259A)
SeeAlso: PORT 0020h-003Fh"PIC 1",INT 70"IRQ8",INT 77"IRQ15"
00A0 RW PIC 2 same as 0020 for PIC 1
00A1 RW PIC 2 same as 0021 for PIC 1 except for OCW1 (see #P124)
Bitfields for PIC2 output control word OCW1:
Bit(s) Description (Table P124)
7 disable IRQ15 (reserved)
6 disable IRQ14 (fixed disk interrupt)
5 disable IRQ13 (coprocessor exception interrupt)
4 disable IRQ12 (mouse interrupt)
3 disable IRQ11 (reserved)
2 disable IRQ10 (reserved)
1 disable IRQ9 (redirect cascade)
0 disable IRQ8 (real-time clock interrupt)
SeeAlso: #P014
----------P00A0------------------------------
PORT 00A0 - XT - NMI MASK REGISTER
SeeAlso: PORT 0070h,INT 02
00A0 RW NMI mask register (XT only)
bit 7 = 0 NMI signal disabled from reaching CPU
= 1 NMI signal enabled
----------P00B000BF--------------------------
PORT 00B0-00BF - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Notes: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
----------P00B2------------------------------
PORT 00B2 - Intel chipsets - Advanced Power Management Control
Notes: used to pass data between the operating system and the System
Management Interrupt (SMI) handler
writes to this port can cause an SMI; reads can cause STPCLK# to be
asserted (putting the CPU in sleep mode)
supported by 82420EX, 82371, and other Intel chipsets
SeeAlso: PORT 00B3h,#0875
00B2 RW control
----------P00B3------------------------------
PORT 00B3 - Intel chipsets - Advanced Power Management Status
Notes: used to pass data between the operating system and the System
Management Interrupt (SMI) handler
supported by 82420EX, 82371, and other Intel chipsets
SeeAlso: PORT 00B2h
00B3 RW status
----------P00C0------------------------------
PORT 00C0 - TI SN746496 programmable tone/noise generator (PCjr)
----------P00C000DF--------------------------
PORT 00C0-00DF - DMA 2 - SECOND DIRECT MEMORY ACCESS CONTROLLER (8237)
00C0 RW DMA channel 4 memory address bytes 1 and 0 (low) (ISA, EISA)
00C2 RW DMA channel 4 transfer count bytes 1 and 0 (low) (ISA, EISA)
00C4 RW DMA channel 5 memory address bytes 1 and 0 (low) (ISA, EISA)
00C6 RW DMA channel 5 transfer count bytes 1 and 0 (low) (ISA, EISA)
00C8 RW DMA channel 6 memory address bytes 1 and 0 (low) (ISA, EISA)
00CA RW DMA channel 6 transfer count bytes 1 and 0 (low) (ISA, EISA)
00CC RW DMA channel 7 memory address byte 0 (low), then 1 (ISA, EISA)
00CE RW DMA channel 7 transfer count byte 0 (low), then 1 (ISA, EISA)
00D0 R- DMA channel 4-7 status register (ISA, EISA) (see #P125)
00D0 -W DMA channel 4-7 command register (ISA, EISA) (see #P126)
00D2 -W DMA channel 4-7 write request register (ISA, EISA)
00D4 -W DMA channel 4-7 write single mask register (ISA, EISA) (see #P128)
00D6 -W DMA channel 4-7 mode register (ISA, EISA) (see #P129)
00D8 -W DMA channel 4-7 clear byte pointer flip-flop (ISA, EISA)
00DA R- DMA channel 4-7 read temporary register (ISA, EISA)
00DA -W DMA channel 4-7 master clear (ISA, EISA)
00DC -W DMA channel 4-7 clear mask register (ISA, EISA)
00DE -W DMA channel 4-7 write mask register (ISA, EISA) (see #P130)
Notes: the temporary register is used as holding register in memory-to-memory
DMA transfers; it holds the last transferred byte
channel 4 is used for cascading the first (8-bit) DMA controller
base/current address registers can only address the memory in 16-bit
words (i.e. they contain lines A1-A16 of the address bus with line
A0 always equal to 0); base/current word count registers contain the
number of 16-bit words
command and request registers do not exist on PS/2 DMA controller
Bitfields for DMA channel 4-7 status register:
Bit(s) Description (Table P125)
7 = 1 channel 7 request
6 = 1 channel 6 request
5 = 1 channel 5 request
4 = 1 channel 4 request
3 = 1 terminal count on channel 7
2 = 1 terminal count on channel 6
1 = 1 terminal count on channel 5
0 = 1 terminal count on channel 4
SeeAlso: #P001,#P126
Bitfields for DMA channel 4-7 command register:
Bit(s) Description (Table P126)
7 DACK sense active high
6 DREQ sense active high
5 =1 extended write selection
=0 late write selection
4 rotating priority instead of fixed priority
3 compressed timing
2 =1 enable controller
=0 enable memory-to-memory transfer
1-0 channel number (00 = 4 to 11 = 7)
SeeAlso: #P002,#P125,#P128
Bitfields for DMA channel 4-7 request register:
Bit(s) Description (Table P127)
7-3 reserved (0)
2 =0 clear request bit
=1 set request bit
1-0 channel number
00 channel 4 select
01 channel 5 select
10 channel 6 select
11 channel 7 select
SeeAlso: #P003,#P128
Bitfields for DMA channel 4-7 write single mask register:
Bit(s) Description (Table P128)
7-3 reserved
2 =0 clear mask bit
=1 set mask bit
1-0 channel select
00 channel 4 select
01 channel 5 select
10 channel 6 select
11 channel 7 select
SeeAlso: #P004,#P126
Bitfields for DMA channel 4-7 mode register:
Bit(s) Description (Table P129)
7-6 transfer mode
00 demand mode
01 single mode
10 block mode
11 cascade mode
5 direction
0 address increment select
1 address decrement select
4 autoinitialisation enabled
3-2 operation
00 verify operation
01 write to memory
10 read from memory
11 reserved
1-0 channel number
00 channel 4 select
01 channel 5 select
10 channel 6 select
11 channel 7 select
SeeAlso: #P005,#P128
Bitfields for DMA channel 4-7 write mask register:
Bit(s) Description (Table P130)
7-4 reserved
3 channel 7 mask bit
2 channel 6 mask bit
1 channel 5 mask bit
0 channel 4 mask bit
Note: each mask bit is automatically set when the corresponding channel
reaches terminal count or an extenal EOP sigmal is received
SeeAlso: #P128,#P006
----------P00E000E1--------------------------
PORT 00E0-00E1 - CHIPSET FROM ACT
00E0 ?W index for accesses to data port
00E1 R? chip set data
----------P00E000E7--------------------------
PORT 00E0-00E7 - MICROCHANNEL
00E0 RW split address register, memory encoding registers PS/2m80 only
(see #P131)
00E1 RW memory register (see #P132,#P133)
00E3 RW error trace (bits 23-16 of address on last rising edge of ERS line)
00E4 RW error trace (bits 15-8 of address on last rising edge of ERS line)
00E5 RW error trace (see #P134)
00E7 RW error trace (see #P135)
Bitfields for Microchannel Split Address Register:
Bit(s) Description (Table P131)
7-6 unused
5-4 2MB memory for connector 2 on Type2 motherboard
bit 5: second MB disabled or not present
bit 4: first MB disabled or not present
3-0 address at which to place leftover from split in first MB, in MB
(1-15, 0 is invalid when split is active)
SeeAlso: #P132,#P133
Bitfields for Microchanel Memory Register, Type1 motherboard:
Bit(s) Description (Table P132)
7-6 1 MB memory for connector 2
10 installed
11 not installed
5-4 1 MB memory for connector 1
10 installed
11 not installed
3-1 split memory select
ROM convmem over1M
001 ON 640K 384K
011 ON 512K 512K
100 shadow 640K 0K
101 ON 640K 0K
110 shadow 512K 0K
111 ON 512K 0K
0 parity checking
=0 enable
=1 clear parity error (write 0 to re-enable parity checking)
SeeAlso: #P131,#P133
Bitfields for Microchannel Memory Register, Type2 motherboard:
Bit(s) Description (Table P133)
7-6 unused
5-4 memory connector 1
bit 5: second MB disabled or not present
bit 4: first MB disabled or not present
3-1 split memory select
ROM convmem over1M
000 shadow 640K 256K
001 ON 640K 384K
010 shadow 512K 384K
011 ON 512K 512K
100 shadow 640K 0K
101 ON 640K 0K
110 shadow 512K 0K
111 ON 512K 0K
0 parity checking
=0 enable
=1 clear parity error (write 0 to re-enable parity checking)
SeeAlso: #P131,#P132
Bitfields for Microchannel Error Trace register E5h:
Bit(s) Description (Table P134)
7-2 bits 7-2 of address on last rising edge of ERS line
1 address space (0=I/O, 1=memory)
0 =1 bus-master arbitration cycle
SeeAlso: #P135
Bitfields for Microchannel Error Trace register E7h:
Bit(s) Description (Table P135)
7-1 unused
0 bus cycle type
=0 control (instruction fetch, halt, interrupt acknowledge)
=1 data
SeeAlso: #P134
----------P00E000EF--------------------------
PORT 00E0-00EF - IBM PS/1 CLOCK
----------P00E1------------------------------
PORT 00E1 - STB PowerMEG - ???
Desc: the STB PowerMEG is a memory expansion card capable of providing EMS
00E1 RW ???
bit 0: ???
----------P00EB------------------------------
PORT 00EB - Intel "Triton" chipset - ???
SeeAlso: PORT 0085h"Triton"
00EB ?W ???
----------P00EB------------------------------
PORT 00EB - DUMMY PORT FOR DELAY???
Note: on a number of machines, the BIOS appears to write a copy of any
data sent to numerous other ports to this port as well; it seems
to be a dummy port used for short delays between writes to other
ports (used instead of JMP $+2, which no longer delays on Pentium+)
SeeAlso: PORT 00ED"DUMMY"
00EB ?W ???
----------P00EC00ED--------------------------
PORT 00EC-00ED - Compaq LTE Elite
----------P00ED------------------------------
PORT 00ED - DUMMY PORT FOR DELAY???
Note: on a number of machines, the BIOS appears to write a copy of any
data sent to numerous other ports to this port as well; it seems
to be a dummy port used for short delays between writes to other
ports (used instead of JMP $+2, which no longer delays on Pentium+)
SeeAlso: PORT 00EB"DUMMY"
00EDw ?W ???
----------P00EF------------------------------
PORT 00EF - Hyunday Super-NB386S (AMD386sx with Intel chipset)
Warning: any access to this port causes a cold reset on this machine!
----------P00F000F5--------------------------
PORT 00F0-00F5 - PCjr Disk Controller
00F0 ?? disk controller
00F2 ?? disk controller control port
00F4 ?? disk controller status register
00F5 ?? disk controller data port
----------P00F000FF--------------------------
PORT 00F0-00FF - MATH COPROCESSOR (8087..80387)
00F0 -W math coprocessor clear busy latch (write 00h)
00F1 -W math coprocessor reset (write 00h)
00F8 RW opcode transfer (CPU-coprocessor communication)
00FA RW opcode transfer
00FC RW opcode transfer
----------P00F9------------------------------
PORT 00F9 - Compaq LTE Elite
----------P00FB------------------------------
PORT 00FB - Compaq LTE Elite
----------P00F900FF--------------------------
PORT 00F9-00FF - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Notes: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
----------P0100------------------------------
PORT 0100 - 3COM 3C509 Ethernet card - ID port
Note: this port is present only on the 3C509, not on any other 3COM card
SeeAlso: PORT 0110h,PORT 0120h
----------P01000107--------------------------
PORT 0100-0107 - PS/2 POS (Programmable Option Select)
Note: the default value for PORT 0102h is stored in CMOS 31h
0100 R POS register 0 Low adapter ID byte
0101 R POS register 1 High adapter ID byte
0102 RW POS register 2 option select data byte 1 (see #P136)
0103 RW POS register 3 option select data byte 2
0104 RW POS register 4 option select data byte 3
0105 RW POS register 5 option select data byte 4
bit 7 channel active (-CHCK)
bit 6 channel status
0106 RW POS register 6 Low subaddress extension
0107 RW POS register 7 High subaddress extension
Bitfields for PS/2 POS register 2, option select data byte 1:
Bit(s) Description (Table P136)
7 0 = unidirectional LPT port
1 = bidirectional LPT port
6-5 PS/2 Model 50 and higher
00b = default LPT port at 3BCh
01b = "" 378h
10b = "" 278h
11b = reserved
4 enable parallel port
3 serial port address
=0 COM2 (02F8h, IRQ3)
=1 COM1 (03F8h, IRQ4)
2 enable serial port
1 enable diskette controller
0 (MCA) =0 override bits 1,2,4 and disable devices
0 card enable (CDEN)
0 =1 VGA sleep bit, disconnects output drivers from VGA (usage for VGA
without monitor)
---ET4000---
7-4 reserved???
3 video RAM wait enable
2 ET4000: ROM BIOS wait enable
1 ET4000: I/O wait enable
Note: access to this port is only possible when PORT 0094h bit 7 is low.
----------P0100010F--------------------------
PORT 0100-010F - CompaQ Tape drive adapter. alternate address at 0300
----------P0108010F--------------------------
PORT 0108-010F - IBM PS/2 - 8 digit LED info panel
010F -W leftmost character on display
010E -W second character
...
0108 -W eighth character
----------P0110------------------------------
PORT 0110 - 3COM 3C509 Ethernet card - ID port (alternate address)
Note: this port is present only on the 3C509, not on any other 3COM card
SeeAlso: PORT 0100h"3COM",PORT 0120h"3COM"
----------P0120------------------------------
PORT 0120 - 3COM 3C509 Ethernet card - ID port (alternate address)
Note: this port is present only on the 3C509, not on any other 3COM card
SeeAlso: PORT 0100h"3COM",PORT 0110h"3COM"
----------P0130013F--------------------------
PORT 0130-013F - CompaQ SCSI adapter. alternate address at 0330
----------P01300133--------------------------
PORT 0130-0133 - Adaptec 154xB/154xC SCSI adapter.
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
----------P01340137--------------------------
PORT 0134-0137 - Adaptec 154xB/154xC SCSI adapter.
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
----------P0138013F--------------------------
PORT 0138-013F - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Notes: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
----------P0140014F--------------------------
PORT 0140-014F - SCSI (alternate Small Computer System Interface) adapter
Note: first adapter is at 0340-034F
----------P0140014F--------------------------
PORT 0140-014F - Xirlink/Relialogic XL-220/221 SCSI adapter
Range: alternate address at 0150, 0160, 0170
Notes: XL-220/221 are based on LOGIC Devices L53C80JC4 SCSI controller which
is compatible with Symbios Logic (formaerly NCR) 53C80
each SCSI data pin is inverted and compared with correcponding bit
in the ID select register; if any matches are found while a bus free
condition exists and SEL is active, SCSI controller will genarate an
interrupt to indicate a selection or reselection
pseudo-DMA register is provided by some on-card PLM, and decodes any
address in the range 01x8-01xF; it should be accessed with 16-bit
I/O instructions only causing 2 SCSI REQ/ACK hanshakes (8-bit I/O
is treated as 16-bit, and second byte is lost); delayed assertion of
the REQ signal or bus free condition on the SCSI bus causes the
pseudo-DMA register to prolong ISA I/O cycle not asserting IOCHRDY
signal (SCSI phase mismatch doesn't), and so may cause ISA bus to
hang in not ready state!
SCSI BIOS is an 8K ROM located at C8000-CBFFF if I/O port range
0140-014F is selected, at CC000-CFFFF if I/O port range 0150-015F
is selected, at D8000-DBFFF if I/O port range 0160-016F is selected,
and at DC000-DFFFF if I/O port range 0170-017F is selected
0140 R- current SCSI data bus register
0140 -W output data register
0141 RW initiator command register (see #P137)
0142 RW mode register (see #P138)
0143 RW target command register (see #P139)
0144 R- current SCSI control register (see #P140)
0144 -W ID select register
0145 R- DMA status register (see #P141)
0145 -W start DMA send register
any write starts DMA send
0146 R- input data register
temporarily holds data byte received from the SCSI bus in DMA mode
0146 -W start DMA target receive register
any write starts target mode DMA receive
0147 R- reset error/interrupt register
any read resets the interrupt request latch and the error latches
0147 -W start DMA initiator mode receive register
any write starts initiator mode DMA receive
0148w RW pseudo-DMA register
Bitfields for initiator command register:
Bit(s) Description (Table P137)
7 assert RST
6 (read) arbitration in progress
(write) test mode
5 (read) lost arbitration
4 assert ACK
3 assert BSY
2 assert SEL
1 assert ATN
0 assert data bus
SeeAlso: #P138,#P139,#P140,#P141
Bitfields for mode register:
Bit(s) Description (Table P138)
7 block mode
6 target mode
5 enable parity check
4 enable parity interrupt
3 enable end of DMA interrupt
2 monitor BSY
1 DMA mode
0 arbitrate
SeeAlso: #P137
Bitfields for target command register:
Bit(s) Description (Table P139)
7 (read) last byte sent
6-4 reserved
3 assert REQ
2 assert MSG
1 assert C/D
0 assert I/O
SeeAlso: #P137
Bitfields for current SCSI control register:
Bit(s) Description (Table P140)
7 RST
6 BSY
5 REQ
4 MSG
3 C/D
2 I/O
1 SEL
0 parity
SeeAlso: #P137
Bitfields for DMA status register:
Bit(s) Description (Table P141)
7 end of DMA
6 DMA request
5 parity error
4 interrupt request
3 phase match
2 BSY error
1 ATN
0 ACK
SeeAlso: #P137
----------P0140014F--------------------------
PORT 0140-014F - Future Domain TMC-16x0 SCSI adapter
Range: alternate address at 0150, 0160, 0170
Notes: TMC-1650/1670 have a 25-pin external connector, whereas the 1660 and
1680 have a SCSI-2 50-pin high-density external connector
TMC-1670/1680 have floppy disk controller built in
BIOS versions prior to 3.2 assigned SCSI ID 6 to SCSI adapter,
versions 3.2 and greater use SCSI ID 7
the drive ordering implemented in BIOS versions 3.4 and 3.5 is the
opposite of the order (currently) used by the rest of the SCSI
industry--for example, under DOS SCSI ID 0 will be D: and SCSI ID 1
will be C:
Future Domain TMC-16x0 SCSI adapter series are based upon Future Domain
TMC-1800/18C50/18C30 SCSI controllers
TMC-1800/18C50/18C30 are ISA SCSI controllers, TMC-36C70 is a PCI
version of TMC-18C30
TMC-1800/18C50 have 8K FIFO, TMC-18C30/36C70 have 2K FIFO
Future Domain TMC-1650/1660/1670/1680/1610M/1610MER/1610MEX SCSI
adapters are based on TMC-1800/18C50/18C30
Quantum ISA-200S/250MG SCSI adapters are based on TMC-18C50 (?)
Future Domain TMC-3260 and Adaptec AHA-2920 PCI SCSI adapters are
based on TMC-36C70
0140 R- read SCSI data register
0140 -W write SCSI data register
0141 R- SCSI status register (see #P142)
0141 -W SCSI control register (see #P143)
0142 R- TMC status register (see #P144)
0142 -W interrupt control register (see #P145)
0143 R- FIFO status register, TMC-18C50/18C30/36C70 chips only
0143 -W SCSI mode control register (see #P146)
0144 R- interrupt condition register, TMC-18C50/18C30/36C70 only (see #P147)
0144 -W TMC control register (see #P148)
0145 R- ID code LSB register
27h for TMC-1800 chip
E9h for TMC-18C50/18C30/36C70 chips
0145 -W memory control register, TMC-18C50/18C30/36C70 only
0146 R- ID code MSB register
60h for TMC-18C50/18C30 chips
61h for TMC-1800 chip
0147 R- read loopback register
0147 -W write loopback register
0148 RW SCSI data no ACK register
0149 R- interrupt status register (see #P149)
014A R- configuration register 1 (see #P150)
014B R- configuration register 2, TMC-18C50/18C30/36C70 only (see #P151)
014B -W I/O control register, TMC-18C30/36C70 only (see #P152)
014Cw R- read FIFO data register
014Cw -W write FIFO data register
014Ew R- FIFO data count register
Notes: any value written into the write loopback register can be read back
from the read loopback register unchanged (this is used by the BIOS
to test the controller)
reading from read SCSI data register and writing to write SCSI data
register causes REQ/ACK handshake to occur automatically, reading
and writing the SCSI data no ACK register doesn't
SCSI FIFO may be used only for DATA IN / DATA OUT phase transfers on
TMC-1800; on TMC-18C50/18C30 it may also be used for COMMAND phase
transfers
Bitfields for SCSI status register:
Bit(s) Description (Table P142)
7 not BSY
6 not MSG
5 not I/O
4 not C/D
3 not REQ
2 not SEL
1 parity error???
0 not ATN
SeeAlso: #P143,#P152
Bitfields for SCSI control register:
Bit(s) Description (Table P143)
7 RST
6 SEL
5 BSY
4 ATN
3 I/O
2 C/D
1 MSG
0 bus enable
SeeAlso: #P142,#P144,#P145
Bitfields for TMC status register:
Bit(s) Description (Table P144)
7 bus enabled
6 parity enabled
5 FIFO enabled
4 =1 data are expected to flow out from FIFO to SCSI bus
=0 data are expected to flow from SCSI bus into FIFO
3 SCSI reset
2 ???
1 arbitration complete
0 interrupt request
SeeAlso: #P143
Bitfields for interrupt control register:
Bit(s) Description (Table P145)
7 enable interrupt on REQ
6 enable interrupt on SEL
5 enable arbitration interrupt
4 enable interrupt on ???
0-3 FIFO threshold (how many 512 byte blocks in FIFO should be
full/empty for interrupt to be generated)
SeeAlso: #P143
Bitfields for SCSI mode control register:
Bit(s) Description (Table P146)
7 synchronous mode
6 fast SCSI
5-4 reserved?
3-0 synchronous transfer period in 25 ns units
SeeAlso: #P143
Bitfields for interrupt condition register:
Bit(s) Description (Table P147)
7 FIFO error interrupt
6 forced interrupt???
5 interrupt on RST
4 arbitration interrupt
3 interrupt on SEL
2 interrupt on REQ
1 interrupt on ???
0 ???
SeeAlso: #P143
Bitfields for TMC control register:
Bit(s) Description (Table P148)
7 enable FIFO
6 =1 data are expected to flow out from FIFO to SCSI bus
=0 data are expected to flow from SCSI bus into FIFO
5 clear forced interrupt, TMC-18C50/18C30/36C70 only
4 enable interrupt
3 enable parity
2 arbitrate
1 force interrupt???
0 clear SCSI reset flag???
SeeAlso: #P143
Note: on the TMC-1800 the FIFO must be enabled and bit 6 must be set
according to the expected data direction before a data phase will
occur (the TMC-1800 probably doesn't generate interrupts on REQ in
DATA IN / DATA OUT phases); on the TMC-18C50/18C30 it may be done
when the interrupt on REQ occurs and the SCSI phase is
DATA IN, DATA OUT or COMMAND
Bitfields for interrupt status register:
Bit(s) Description (Table P149)
7 interrupt on REQ enabled
6 interrupt on SEL enabled
5 arbitration interrupt enabled
4 interrupt on ??? enabled
3 interrupt enabled
2 ???
1 always set???
0 ???
SeeAlso: #P143
Bitfields for configuration register 1:
Bit(s) Description (Table P150)
7-6 BIOS address range
00 C8000h-C9FFFh
01 CA000h-CBFFFh
10 CE000h-CFFFFh
11 DE000h-DFFFFh
5-4 I/O address range
00 140h-14Fh
01 150h-15Fh
10 160h-16Fh
11 170h-17Fh
3-1 interrupt select
000 IRQ3
001 IRQ5
010 IRQ10
011 IRQ11
100 IRQ12
101 IRQ14
110 IRQ15
111 no IRQ
0 reserved???
Note: the seven on-board configuration jumpers are read through this register
SeeAlso: #P143,#P151
Bitfields for configuration register 2:
Bit(s) Description (Table P151)
7 32-bit mode enabled (TMC-18C30/36C70 only???)
6-2 ???
1 RAM disabled (TMC-18C30/36C70 only???)
0 ???
Note: 256 byte on-chip RAM is mapped at offset 1F00h within the BIOS segment
SeeAlso: #P143,#P150
Bitfields for TMC control register:
Bit(s) Description (Table P152)
7 enable 32-bit mode
6-0 ???
SeeAlso: #P143
--------d-P0140014F--------------------------
PORT 0140-014F - Quantum ISA-200S/250MG SCSI adapter
Range: alternate address at 0150, 0160, 0170
Note: Quantum ISA-200S/250MG SCSI adapters are based upon Future Domain
TMC-18C50 SCSI controller (???)
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
----------P01400157--------------------------
PORT 0140-0157 - RTC (alternate Real Time Clock for XT) (1st at 0340-0357)
----------P0150015F--------------------------
PORT 0150-015F - Xirlink/Relialogic XL-220/221 SCSI adapter
Range: alternate address at 0140, 0160, 0170
----------P0150015F--------------------------
PORT 0150-015F - Future Domain TMC-16x0 SCSI adapter
Range: alternate address at 0140, 0160, 0170
--------d-P0150015F--------------------------
PORT 0150-015F - Quantum ISA-200S/250MG SCSI adapter
Range: alternate address at 0140, 0160, 0170
Note: Quantum ISA-200S/250MG SCSI adapters are based upon Future Domain
TMC-18C50 SCSI controller (???)
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
----------P015C015D--------------------------
PORT 015C-015D - Dell Enhanced Parallel Port
SeeAlso: PORT 002Eh,PORT 026Eh,PORT 0398h
015C -W index for data port
015D RW EPP command data
----------P015F------------------------------
PORT 015F - ARTEC Handyscanner A400Z. alternate address at 35F.
----------P0160016F--------------------------
PORT 0160-016F - Xirlink/Relialogic XL-220/221 SCSI adapter
Range: alternate address at 0140, 0150, 0170
----------P0160016F--------------------------
PORT 0160-016F - Future Domain TMC-16x0 SCSI adapter
Range: alternate address at 0140, 0150, 0170
--------d-P0160016F--------------------------
PORT 0160-016F - Quantum ISA-200S/250MG SCSI adapter
Range: alternate address at 0140, 0150, 0170
Note: Quantum ISA-200S/250MG SCSI adapters are based upon Future Domain
TMC-18C50 SCSI controller (???)
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
----------P0168016F--------------------------
PORT 0168-016F - 4th (Quaternary) EIDE Controller
Range: 01F0-01F7 for primary controller, 0170-0177 for secondary controller
SeeAlso: PORT 0170h-0177h,PORT 01E8h-01EFh,PORT 01F0h-01F7h
----------P01700177--------------------------
PORT 0170-0177 - HDC 2 (2nd Fixed Disk Controller) (ISA, EISA)
Range: 01F0-01F7 for primary controller, 0170-0177 for secondary controller
SeeAlso: PORT 0168h-016Fh,PORT 01E8h-01EFh,PORT 01F0h-01F7h
----------P0170017F--------------------------
PORT 0170-017F - Xirlink/Relialogic XL-220/221 SCSI adapter
Range: alternate address at 0140, 0150, 0160
----------P0170017F--------------------------
PORT 0170-017F - Future Domain TMC-16x0 SCSI adapter
Range: alternate address at 0140, 0150, 0160
--------d-P0170017F--------------------------
PORT 0170-017F - Quantum ISA-200S/250MG SCSI adapter
Range: alternate address at 0140, 0150, 0160
Note: Quantum ISA-200S/250MG SCSI adapters are based upon Future Domain
TMC-18C50 SCSI controller (???)
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
----------P01780179--------------------------
PORT 0178-0179 - Power Management
SeeAlso: PORT 0026h,#P086
0178 -W index selection for data port
0179 RW power management data
----------P0178017F--------------------------
PORT 0178-017F - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Notes: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
----------P01CE01CF--------------------------
PORT 01CE-01CF - ATI Mach32 video chipset - ???
01CE -W index register
01CF RW data register
----------P01E801EF--------------------------
PORT 01E8-01EF - Headland HL21 & Acer M5105 chipsets - SYSTEM CONTROL
01ED RW select internal register. Data to/from 01EF
01EE R- ???
01EF RW register value
05h = 1000xxxx for low CPU clock speed (4MHz on Morse/Mitac)
= 0xxxxxxx for high CPU clock speed (16MHz on Morse/Mitac)
10h memory size
bits 2-0 = size
(undefined,512K,640K,1024K,2560K,2048K,4096K,undef.)
14h ???
bit 2: 384K RAM of first 1024K relocated to top of memory
----------P01E801EF--------------------------
PORT 01E8-01EF - 3rd (Tertiary) EIDE Controller
Range: 01F0-01F7 for primary controller, 0170-0177 for secondary controller
SeeAlso: PORT 0168h-016Fh,PORT 0170h-0177h,PORT 01F0h-01F7h
----------P01F001F7--------------------------
PORT 01F0-01F7 - HDC 1 (1st Fixed Disk Controller) (ISA, EISA)
Range: 01F0-01F7 for primary controller, 0170-0177 for secondary controller
SeeAlso: PORT 0170h-0177h,PORT 3510h-3513h
01F0 RW data register
01F1 R- error register (see #P153)
01F1 -W WPC/4 (Write Precompensation Cylinder divided by 4)
01F2 RW sector count
01F3 RW sector number (CHS mode)
logical block address, bits 0-7 (LBA mode)
01F4 RW cylinder low (CHS mode)
logical block address, bits 15-8 (LBA mode)
01F5 RW cylinder high (CHS mode)
logical block address, bits 23-16 (LBA mode)
01F6 RW drive/head (see #P154)
01F7 R- status register (see #P155)
01F7 -W command register (see #P156)
Bitfields for Hard Disk Controller error register:
Bit(s) Description (Table P153)
---diagnostic mode errors---
7 which drive failed (0 = master, 1 = slave)
6-3 reserved
2-0 error code
001 no error detected
010 formatter device error
011 sector buffer error
100 ECC circuitry error
101 controlling microprocessor error
---operation mode---
7 bad block detected
6 uncorrectable ECC error
5 reserved
4 ID found
3 reserved
2 command aborted prematurely
1 track 000 not found
0 DAM not found (always 0 for CP-3022)
SeeAlso: #P154,#P155
Bitfields for hard disk controller drive/head specifier:
Bit(s) Description (Table P154)
7 =1
6 LBA mode enabled, rather than default CHS mode
5 =1
4 drive select (0 = drive 0, 1 = drive 1)
3-0 head select bits (CHS mode)
logical block address, bits 27-24 (LBA mode)
SeeAlso: #P153,#P155
Bitfields for hard disk controller status register:
Bit(s) Description (Table P155)
7 controller is executing a command
6 drive is ready
5 write fault
4 seek complete
3 sector buffer requires servicing
2 disk data read successfully corrected
1 index - set to 1 each disk revolution
0 previous command ended in an error
SeeAlso: #P153,#P156
(Table P156)
Values for hard disk controller command codes:
Command Spec Type Proto Description class:
00h opt nondata NOP
08h device reset
1xh opt nondata recalibrate 1
20h req PIOin read sectors with retry 1
21h req PIOin read sectors without retry 1
22h req PIOin read long with retry 1
23h req PIOin read long without retry 1
30h req PIOout write sectors with retry 2
31h req PIOout write sectors without retry 2
32h req PIOout write long with retry 2
33h req PIOout write long without retry 2
3Ch IDE opt PIOout write verify 3
40h req nondata read verify sectors with retry 1
41h req nondata read verify sectors without retry 1
50h req vend format track 2
7xh req nondata seek 1
8xh IDE vendor vend vendor unique 3
90h req nondata execute drive diagnostics 1
91h req nondata initialize drive parameters 1
92h opt PIOout download microcode
94h E0h IDE opt nondata standby immediate 1
95h E1h IDE opt nondata idle immediate 1
96h E2h IDE opt nondata standby 1
97h E3h IDE opt nondata idle 1
98h E5h IDE opt nondata check power mode 1
99h E6h IDE opt nondata set sleep mode 1
9Ah IDE vendor vend vendor unique 1
A0h ATAPI packet command
A1h ATAPI opt PIOin ATAPI Identify (see #P165)
B0h SMART opt Self Mon., Analysis, Rept. Tech. (see #P167)
C0h-C3h IDE vendor vend vendor unique 2
C4h IDE opt PIOin read multiple 1
C5h IDE opt PIOout write multiple 3
C6h IDE opt nondata set multiple mode 1
C7h ATA-4 Read DMA O/Q
C8h IDE opt DMA read DMA with retry 1
C9h IDE opt DMA read DMA without retry 1
CAh IDE opt DMA write DMA with retry 3
CBh IDE opt DMA write DMA w/out retry 3
CCh ATA-4 Write DMA O/Q
DAh get media status
DBh ATA-2 opt vend acknowledge media chng [Removable]
DCh ATA-2 opt vend Boot / Post-Boot [Removable]
DDh ATA-2 opt vend Boot / Pre-Boot (ATA-2) [Removable]
DEh ATA-2 opt vend door lock [Removable]
DFh ATA-2 opt vend door unlock [Removable]
E0h-E3h (second half of commands 94h-96h)
E4h IDE opt PIOin read buffer 1
E5h-E6h (second half of commands 98h-99h)
E8h IDE opt PIOout write buffer 2
E9h IDE opt PIOout write same 3
EAh ATA-3 opt Secure Disable [Security Mode]
EAh ATA-3 opt Secure Lock [Security Mode]
EAh ATA-3 opt Secure State [Security Mode]
EAh ATA-3 opt Secure Enable WriteProt [Security Mode]
EBh ATA-3 opt Secure Enable [Security Mode]
EBh ATA-3 opt Secure Unlock [Security Mode]
ECh IDE req PIOin identify drive 1 (see #P157)
EDh ATA-2 opt nondata media eject [Removable]
EEh ATA-3 opt identify device DMA (see #P157)
EFh IDE opt nondata set features 1 (see #P175)
F0h-F4h IDE vend EATA standard
F1h Security Set Password
F2h Security Unlock
F3h Security Erase Prepare
F4h Security Erase Unit
F5h-FFh IDE vendor vend vendor unique 4
F5h Security Freeze Lock
F6h Security Disable Password
SeeAlso: #P153,#P155
Format of IDE/ATA Identify Drive information:
Offset Size Description (Table P157)
00h WORD general configuration (see #P158)
02h WORD number of logical cylinders
04h WORD reserved
06h WORD number of logical heads
08h WORD vendor-specific (obsolete: unformatted bytes per track)
0Ah WORD vendor-specific (obsolete: unformatted bytes per sector)
0Ch WORD number of logical sectors
0Eh WORD vendor-specific
10h WORD vendor-specific
12h WORD vendor-specific
14h 10 WORDs serial number
no serial number if first word is 0000h
else blank-padded ASCII serial number
28h WORD vendor-specific
[buffer type: 01h single-sector, 02h multisector,
03h multisector with read cache]
2Ah WORD controller buffer size in 512-byte sectors
0000h = unspecified
2Ch WORD number of vendor-specific (usually ECC) bytes on
Read/Write Long; 0000h = unspecified
2Eh 4 WORDs firmware revision
no revision number if first word is 0000h
else blank-padded ASCII revision number
36h 20 WORDs model number
no model number if first word is 0000h
else blank-padded ASCII model string
5Eh WORD read/write multiple support
bits 7-0: maximum number of sectors per block supported
00h if read/write multiple not supported
bits 15-8: vendor-specified
60h WORD able to do doubleword transfers if nonzero
62h WORD capabilities (see #P159)
64h WORD security mode
bit 15: security-mode feature set supported
bits 14-8: maximum number of passwords supported
66h WORD PIO data transfer cycle timing
68h WORD single-word DMA data transfer cycle timing
6Ah WORD field validity
bit 0: offsets 6Ch-75h valid
bit 1: offsets 80h-8Dh valid
6Ch WORD logical cylinders in current translation mode
6Eh WORD logical heads in current translation mode
70h WORD logical sectors per track in current translation mode
72h DWORD current capacity in sectors (excluding device-specific uses)
76h WORD multiple-sector support
bits 7-0: count for read/write multiple command
bit 8: multiple-sector setting is valid
78h DWORD total number of user-addressable sectors (LBA mode)
00000000h if LBA mode not supported
7Ch WORD single-word DMA transfer modes
low byte is bitmap of supported modes (bit 0 = mode 0, etc.)
high bytes is bitmap of active mode (bit 8 = mode 0, etc.)
7Eh WORD multiword DMA transfer
low byte is bitmap of supported modes (bit 0 = mode 0, etc.)
high byte is bitmap of active mode (bit 8 = mode 0, etc.)
80h WORD supported flow control PIO transfer modes
82h WORD minimum multiword DMA transfer cycle time in ns
84h WORD recommended multiword DMA cycle time in ns
86h WORD minimum non-flow-control PIO transfer cycle time in ns
88h WORD minimum PIO transfer cycle time with IORDY in ns
8Ah 2 WORDs reserved for future PIO modes (0)
8Eh 2 WORDs reserved (0)
92h WORD command queueing/overlapped operation (see #P164)
94h 6 WORDs reserved (0)
A0h WORD major revision number of specification to which device conforms
01h = ATA-1, 02h = ATA-2, etc. 0000h/FFFFh = not reported
A2h WORD minor revision number of specification to which device conforms
0000h/FFFFh = not reported
A4h WORD feature set support 1 (see #P160)
(only valid if revision reported in A0h/A2h)
A6h WORD feature set support 2 (see #P161)
(only valid if revision reported in A0h/A2h)
A8h WORD (ATA/ATAPI-4) feature set support extension (see #P162)
AAh WORD feature set enabled 1 (see #P163)
(only valid if revision reported in A0h/A2h)
ACh WORD feature set enabled 2 (see #P161)
(only valid if revision reported in A0h/A2h)
AEh WORD (ATA/ATAPI-4) feature set enabled extension (see #P162)
B0h 42 WORDs reserved (0)
100h 32 WORDs vendor-specific
100h WORD security status
140h 96 WORDs reserved (0)
SeeAlso: #P165,#0199
Bitfields for IDE general configuration:
Bit(s) Description (Table P158)
15 device class
=0 ATA device
=1 ATAPI device
14 requires format speed tolerance gap
13 supports track offset option
12 supports data strobe offset
11 disk rotational sped tolerance > 0.5%
10-8 disk transfer rate
001 <= 5Mbit/sec
010 5-10 Mbit/sec
100 > 10Mbit/sec
7-6 drive type
01 fixed media
10 removable media
5 synchronized drive motor option enabled
4 head-switching time > 15 microseconds
3 encoding
=0 MFM
2-1 sector type
01 hard-sectored
10 soft-sectored
0 unused (0)
SeeAlso: #P157
Bitfields for IDE capabilities:
Bit(s) Description (Table P159)
13 Standby Timer values used according to ATA standard
11 IORDY supported
10 device can disable use of IORDY
9 LBA mode supported
8 DMA supported
SeeAlso: #P157
Bitfields for ATA feature set support 1:
Bit(s) Description (Table P160)
15 Identify Device DMA command is supported
14 NOP (00h) command is supported
13 Read Buffer command is supported
12 Write Buffer command is supported
11 Write Verify command is supported
10 host protected area feature set is supported
9 Device Reset (08h) command is supported
8 Service interrupt is supported
7 release interrupt is supported
6 device supports look-ahead
5 device supports write cache
4 PACKET command feature set is supported
3 power management is supported
2 removable-media feature set is supported
1 security feature set is supported
0 SMART feature set is supported
SeeAlso: #P157,#P161,#P162
Bitfields for ATA feature set support/enabled 2:
Bit(s) Description (Table P161)
15 must be 0 if this field is supported
14 must be 1 if this field is supported
13-2 reserved
1 Read DMA O/Q (C7h) and Write DMA O/Q (CCh) commands supported/enabled
0 Download Microcode (92h) command is supported/enabled
SeeAlso: #P157,#P163,#P160,#P162
Bitfields for ATA feature set support extension:
Bit(s) Description (Table P162)
15 must be 0 if this field is supported
14 must be 1 if this field is supported
13-0 reserved
SeeAlso: #P157,#P160,#P161
Bitfields for ATA feature set enabled 2:
Bit(s) Description (Table P163)
15-1 reserved
0 Download Microcode (92h) command is eanbled
SeeAlso: #P157,#P161
Bitfields for ATA/ATAPI-4 command queueing/overlapped operation support:
Bit(s) Description (Table P164)
15 reserved
14 device supports command queueing
13 device supports overlapped operation
12-5 reserved
4-0 maximum depth of queued commands supported (0 if bit 14 clear)
SeeAlso: #P157
Format of ATAPI Identify Information:
Offset Size Description (Table P165)
00h WORD general configuration (see #P166)
02h 9 WORDs ???
14h 10 WORDs serial number
no serial number if first word is 0000h
else blank-padded ASCII serial number
28h 3 WORDs vendor-specific
2Eh 4 WORDs firmware revision
no revision number if first word is 0000h
else blank-padded ASCII revision number
36h 20 WORDs model number
no model number if first word is 0000h
else blank-padded ASCII model string
5Eh WORD vendor-specific
60h WORD reserved (0)
62h WORD capabilities (see #P159)
64h WORD security mode???
66h WORD PIO data transfer cycle timing
68h WORD single-word DMA data transfer cycle timing
6Ah WORD field validity
bit 0: offsets 6Ch-73h valid
bit 1: offsets 80h-8Dh valid
6Ch WORD ??? logical cylinders in current translation mode
6Eh WORD ??? logical heads in current translation mode
70h WORD ??? logical sectors per track in current translation mode
72h 2 WORDs ??? current capacity in sectors
76h WORD ??? multiple-sector count for read/write multiple command
78h 2 WORDs ??? total number of user-addressable sectors (LBA mode)
7Ch WORD single-word DMA transfer modes
low byte is bitmap of supported modes (bit 0 = mode 0, etc.)
high bytes is bitmap of active mode (bit 8 = mode 0, etc.)
7Eh WORD multiword DMA transfer
low byte is bitmap of supported modes (bit 0 = mode 0, etc.)
high bytes is bitmap of active mode (bit 8 = mode 0, etc.)
80h WORD supported flow control PIO transfer modes
82h WORD minimum multiword DMA transfer cycle time
84h WORD recommended multiword DMA cycle time
86h WORD minimum non-flow-control PIO transfer cycle time
88h WORD minimum PIO transfer cycle time with IORDY
8Ah 2 WORDs reserved for future PIO modes (0)
8Eh WORD typical time for release when processing overlapped CMD in
microseconds
90h WORD ???
92h WORD major ATAPI version number
94h WORD minor ATAPI version number
96h 54 WORDs reserved (0)
100h 32 WORDs vendor-specific
140h 96 WORDs reserved (0)
SeeAlso: #P157
Bitfields for ATAPI General Configuration:
Bit(s) Description (Table P166)
15-14 device type
13 reserved
12 device present
7 device is removable
6-5 CMD DMA Request type
00 microprocessor DRQ
01 interrupt DRQ
10 accelerated DRQ
11 reserved
4-2 reserved
1-0 CMD packet size (00 = 12 bytes, 01 = 16 bytes)
SeeAlso: #P165
(Table P167)
Values for Self-Monitoring, Analysis, Reporting Technology (SMART) subcommand:
D0h Read Attribute Values (optional) (see #P169)
results returned in 512-byte sector read from controller
D1h Read Attribute Thresholds (optional) (see #P168)
results returned in 512-byte sector read from controller
D2h Disable Attribute Autosave (optional)
sector-count register set to 0000h
D2h Enable Attribute Autosave
sector-count register set to 00F1h
D3h Save Attribute Values (optional)
D4h execute off-line tests immediately (optional)
D5h-D6h reserved
D7h vendor-specific
D8h Enable SMART Operations
D9h Disable SMART Operations
DAh Return SMART Status
if any threshold(s) exceeded, CylinderLow set to F4h and CylinderHigh
set to 2Ch
DBh Enable/Disable Automatic Off-Line Data Collection
sector-count register set to 0000h to disable, 00F8h to enable
DCh-DFh reserved
E0h-EFh vendor-specific
Note: to access SMART commands, the Cylinder Low register must be set to
004Fh and the Cylinder High register must be set to 00C2h before
invoking the SMART command with the SMART command number in the
Features register
SeeAlso: #P156
Format of S.M.A.R.T. attribute thresholds sector:
Offset Size Description (Table P168)
00h WORD data structure revision number (0005h for SMART Revision 2.0)
02h 12 BYTEs attribute threshold data 1 (see #P171)
...
14Eh 12 BYTEs attribute threshold data 30 (see #P171)
16Ah 18 BYTEs reserved (0)
17Ch 131 BYTEs vendor-specific
1FFh BYTE checksum (two's complement of eight-bit sum of first 511 bytes)
Note: if the drive provides fewer than 30 attributes, all remaining attribute
records are filled with NUL (00h) bytes
SeeAlso: #P167,#P169
Format of S.M.A.R.T. attribute values sector:
Offset Size Description (Table P169)
00h WORD
02h 12 BYTEs attribute value data 1 (see #P172)
...
14Eh 12 BYTEs attribute value data 30 (see #P172)
16Ah BYTE off-line data collection status (see #P173)
16Bh BYTE vendor-specific
16Ch WORD time to complete off-line data collection, in seconds
0001h-FFFFh
16Eh BYTE vendor-sepcific
16Fh BYTE off-line data collection capability (see #P174)
170h WORD S.M.A.R.T. capabilities (see #P170)
172h 16 BYTEs reserved (0)
182h 125 BYTEs vendor-specific
1FFh BYTE checksum (two's complement of eight-bit sum of first 511 bytes)
Note: if the drive provides fewer than 30 attributes, all remaining attribute
records are filled with NUL (00h) bytes
SeeAlso: #P167,#P168
Bitfields for S.M.A.R.T capabilities:
Bit(s) Description (Table P170)
0 attributes saved on going into power-saving mode
1 Enable/Disable Attribute Autosave subcommands are supported
2-15 reserved
SeeAlso: #P169
Format of S.M.A.R.T. attribute threshold:
Offset Size Description (Table P171)
00h BYTE attribute ID (01h-FFh)
01h BYTE attribute threshold
00h always passing
01h minimum threshold value
FDh maximum threshold value
FEh invalid (do not use)
FFh always failing (for testing)
02h 10 BYTEs reserved (0)
Note: the attribute ID and actual threshold values are vendor-specific
SeeAlso: #P168,#P172
Format of S.M.A.R.T attribute value:
Offset Size Description (Table P172)
00h BYTE attribute ID (01h-FFh)
01h WORD status flags
bit 0: pre-failure/advisory
=0 value < threshold indicates usage/age exceeding
design life
=1 value < threshold indicates pre-failure condition
bit 1: on-line data collection
bits 2-5 vendor-specific
bits 6-15 reserved
03h BYTE attribute value (01h-FDh)
initial value prior to data collection is 64h
04h 8 BYTEs vendor-specific
SeeAlso: #P169,#P171
(Table P173)
Values for S.M.A.R.T. off-line data collection status:
00h off-line collection never started
01h reserved
02h off-line data collection completed successfully
03h reserved
04h off-line data collection suspended by command from host
05h off-line data collection aborted by command from host
06h off-line data collection aborted due to fatal error
07h-3Fh reserved
40h-7Fh vendor-specific
80h off-line collection never started (auto-offline feature enabled)
81h reserved
82h off-line data collection completed successfully (auto-offline feature
enabled)
83h reserved
84h off-line data collection suspended by command from host (auto-offline
feature enabled)
85h off-line data collection aborted by command from host (auto-offline
feature enabled)
86h off-line data collection aborted due to fatal error (auto-offline
feature enabled)
87h-BFh reserved
C0h-FFh vendor-specific
SeeAlso: #P169,#P174
Bitfields for S.M.A.R.T. off-line data collection capabilities:
Bit(s) Description (Table P174)
0 Execute Off-Line Immediate (D4h) subcommand is implemented
1 Enable/Disable Automatic Off-Line subcommand is implemented
2 abort/resume on interrupting command
=0 off-line resumes automatically after an interrupting command
=1 off-line collection is aborted by an interrupting command
3-7 reserved
SeeAlso: #P167
(Table P175)
Values for Feature Code:
01h [opt] 8-bit instead of 16-bit data transfers
02h [opt] enable write cache
03h set transfer mode as specified by Sector Count register
04h [opt] enable all automatic defect reassignment
22h [opt] Write Same, user-specified area
33h [opt] disable retries
44h specify length of ECC bytes used by Read Long and Write Long
54h [opt] set cache segments (value in Sector Count register)
55h disable look-ahead
66h disable reverting to power-on defaults
77h [opt] disable ECC
81h [opt] 16-bit instead of 8-bit data transfers
82h [opt] disable write cache
84h [opt] disable all automatic defect reassignment
88h [opt] enable ECC
99h [opt] enable retries
9Ah [opt] set device maximum average current
AAh enable look-ahead
ABh [opt] set maximum prefecth (value in Sector Count register)
BBh use four bytes of ECC on Read Long and Write Long (for compat.)
CCh enable reverting to power-on defaults
DDh [opt] Write Same, entire disk
SeeAlso: #0198
----------P01F8------------------------------
PORT 01F8 - ???
01F8 RW ???
bit 0: A20 gate control (set = A20 enabled, clear = disabled)
----------P01F901FF--------------------------
PORT 01F9-01FF - PC radio by CoZet Info Systems
Range: The I/O address range is dipswitch selectable from:
038-03F and 0B0-0BF
078-07F and 0F0-0FF
138-13F and 1B0-1BF
178-17F and 1F0-1FF
238-23F and 2B0-2BF
278-27F and 2F0-2FF
338-33F and 3B0-3BF
378-37F and 3F0-3FF
Notes: All of these addresses show a readout of FFh in initial state.
Once started, all of the addresses show FBh, whatever might happen.
--------d-P0200------------------------------
PORT 0200 - Digidesign 'Session 8' HARD-DISK RECORDING SYSTEM
SeeAlso: PORT 0300h"Digidesign"
----------P0200020F--------------------------
PORT 0200-020F - Game port reserved I/O address space
0200-0207 - Game port, eight identical addresses on some boards
0201 R- read joystick position and status (see #P176)
0201 -W fire joystick's four one-shots
0201 RW gameport on mc-soundmachine, mc 03-04/1992: Adlib-compatible,
Covox 'voice master' & 'speech thing' compatible soundcard.
(enabled if bit1=1 in PORT 038Fh. Because it is disabled on
power-on, it cannot be found by BIOS) (see PORT 0388h-038Fh)
Bitfields for joystick position and status:
Bit(s) Description (Table P176)
7 status B joystick button 2 / D paddle button
6 status B joystick button 1 / C paddle button
5 status A joystick button 2 / B paddle button
4 status A joystick button 1 / A paddle button
3 B joystick Y coordinate / D paddle coordinate
2 B joystick X coordinate / C paddle coordinate
1 A joystick Y coordinate / B paddle coordinate
0 A joystick X coordinate / A paddle coordinate
----------P020002FF--------------------------
PORT 0200-02FF - Sunshine uPW48, programmer for EPROM version CPU's 8748/8749
Range: 4 bit DIP switch installable in the range 20x-2Fx
0200-0203 adresses of the 8255 on the uPW48
0208-020B adresses of ??? on the uPW48 (all showing zeros)
----------P02080209--------------------------
PORT 0208-0209 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, 02E8
----------P020C020F--------------------------
PORT 020C-020F - AIMS LAB PC Radio
Range: configurable to PORT 020Ch or PORT 030Ch
Notes: writing a value with bit 3 set to one of these ports turns on the
radio; writing a value with bit 3 clear turns it off
PORT 020Eh bits 1 indicates status of some kind
----------P02100217--------------------------
PORT 0210-0217 - Expansion unit (XT)
0210 -W latch expansion bus data
0210 R- verify expansion bus data
0211 -W clear wait, test latch
0211 R- High byte data address
0212 R- Low byte data address
0213 -W 0=enable, 1=disable expansion unit
0214 -W latch data (receiver card port)
0214 R- read data (receiver card port)
0215 R- High byte of address, then Low byte (receiver card port)
----------P02100211--------------------------
PORT 0210-0211 - Game Blaster
Range: PORT 02x0h-02x1h, x=1,2,...
0210 -W register index
0211 ?W register data
----------P02180219--------------------------
PORT 0218-0219 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P02200223--------------------------
PORT 0220-0223 - Sound Blaster / Adlib port (Stereo)
SeeAlso: PORT 0388h-0389h
0220 R- Left speaker -- Status port
0220 -W Left speaker -- Address port
0221 -W Left speaker -- Data port
0222 R- Right speaker -- Status port
0222 -W Right speaker -- Address port
0223 -W Right speaker -- Data port
----------P02200227--------------------------
PORT 0220-0227 - Soundblaster PRO and SSB 16 ASP
----------P0220022F--------------------------
PORT 0220-022F - Soundblaster PRO 2.0
----------P0220022F--------------------------
PORT 0220-022F - Soundblaster PRO 4.0
Note: the FM music is accessible on 0388/0389 for compatibility.
0220 R- left FM status port
0220 -W left FM music register address port (index)
0221 RW left FM music data port
0222 R- right FM status port
0222 -W right FM music register address port (index)
0223 RW right FM music data port
0224 -W mixer register address port (index)
0225 RW mixer data port
0226 -W DSP reset
0228 R- FM music status port
0228 -W FM music register address port (index)
0229 -W FM music data port
022A R- DSP read data (voice I/O and Midi)
022C -W DSP write data / write command
022C R- DSP write buffer status (bit 7)
022E R- DSP data available status (bit 7)
----------P022B------------------------------
PORT 022B - GI1904 Scanner Interface Adapter
Range: PORT 026Bh, PORT 02ABh (default), PORT 02EBh, PORT 032Bh, PORT 036Bh
Range: PORT 03ABh, PORT 03EBh
----------P022C------------------------------
PORT 022C - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P022F------------------------------
PORT 022F - mc-soundmachine, mc 03-04/1992 - SPEECH I/O
Note: An Adlib-compatible Covox 'voice master' & 'speech thing' compatible
soundcard
SeeAlso: PORT 0378h"Covox",PORT 0388h-038Fh"soundmachine"
022F RW Covox compatible speech I/O (via internal A/D converter,
each read access starts a new conversion cycle)
register enabled if bit7=1 in PORT 038Fh
----------P02300233--------------------------
PORT 0230-0233 - Adaptec 154xB/154xC SCSI adapter.
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
----------P02340237--------------------------
PORT 0234-0237 - Adaptec 154xB/154xC SCSI adapter.
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
----------P0238023F--------------------------
PORT 0238-023F - COM port addresses on UniRAM card by German magazine c't
selectable from 238, 2E8, 2F8, 338, 3E0, 3E8, 3F8
----------P0238023x--------------------------
PORT 0238-023x - Bus Mouse Port (secondary address)
Note: secondary address for bus mice from MS and Logitech, and the ATI
video adapter mouse
SeeAlso: PORT 023Ch"Mouse"
----------P023C023x--------------------------
PORT 023C-023x - Bus Mouse Port (primary address)
Note: primary address for bus mice from MS and Logitech, the ATI video
adapter mouse, and the Commodore PC30III bus mouse
SeeAlso: PORT 0238h"Mouse"
----------P0240024F--------------------------
PORT 0240-024F - Gravis Ultra Sound by Advanced Gravis
Range: The I/O address range is dipswitch selectable from:
0200-020F and 0300-030F
0210-021F and 0310-031F
0220-022F and 0320-032F
0230-023F and 0330-033F
0240-024F and 0340-034F
0250-025F and 0350-035F
0260-026F and 0360-036F
0270-027F and 0370-037F
SeeAlso: PORT 0340h-034Fh,PORT 0746h
0240 -W Mix Control register (see #P177)
0241 R- Read Data
0241 -W Trigger Timer
0246 R- IRQ Status Register (see #P178)
0248 RW Timer Control Reg
Same as ADLIB Board (see PORT 0200h)
0249 -W Timer Data (see #P179)
024B -W IRQ Control Register (0240 bit 6 = 1) (see #P180)
024B -W DMA Control Register (0240 bit 6 = 0) (see #P181)
024F RW Register Controls (rev 3.4+)
Bitfields for Gravis Ultra Sound mix control register:
Bit(s) Description (Table P177)
6 Control Register Select (see 024B)
5 Enable MIDI Loopback
4 Combine GF1 IRQ with MIDI IRQ
3 Enable Latches
2 Enable MIC IN
1 Disable LINE OUT
0 Disable LINE IN
SeeAlso: #P178
Bitfields for Gravis Ultra Sound IRQ status register:
Bit(s) Description (Table P178)
7 DMA TC IRQ
6 Volume Ramp IRQ
5 WaveTable IRQ
3 Timer 2 IRQ
2 Timer 1 IRQ
1 MIDI Receive IRQ
0 MIDI Transmit IRQ
SeeAlso: #P177,#P180,#P181
Bitfields for Gravis Ultra Sound timer data:
Bit(s) Description (Table P179)
7 Reset Timr IRQ
6 Mask Timer 1
5 Mask Timer 2
1 Timer 2 Start
0 Timer 1 Start
SeeAlso: #P178,#P180
Bitfields for Gravis Ultra Sound IRQ control register:
Bit(s) Description (Table P180)
6 Combine Both IRQ
5-3 MIDI IRQ Selector
000 No IRQ
001 IRQ 2
010 IRQ 5
011 IRQ 3
100 IRQ 7
101 IRQ 11
110 IRQ 12
111 IRQ 15
2-0 GF1 IRQ Selector
000 No IRQ
001 IRQ 2
010 IRQ 5
011 IRQ 3
100 IRQ 7
101 IRQ 11
110 IRQ 12
111 IRQ 15
SeeAlso: #P178,#P181
Bitfields for Gravis Ultra Sound DMA Control Register:
Bit(s) Description (Table P181)
6 Combine Both DMA
5-3 DMA Select Register 2
000 No DMA
001 DMA 1
010 DMA 3
011 DMA 5
100 DMA 6
101 DMA 7
2-0 DMA Select Register 1
000 No DMA
001 DMA 1
010 DMA 3
011 DMA 5
100 DMA 6
101 DMA 7
SeeAlso: #P178,#P180,#P221
----------P02400257--------------------------
PORT 0240-0257 - RTC (alternate Real Time Clock for XT) (1st at 0340-0357)
(used by TIMER.COM v1.2 which is the 'standard' timer program)
----------P02580259--------------------------
PORT 0258-0259 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P02580259--------------------------
PORT 0258-0259 - AT RAMBANK Memory Expansion Board - EXT MEMORY AND EMS-SUPPORT
Range: base address may be set to 0218h, 0228h, 0238h, 0258h, 0268h, 0298h,
or 02A8h
----------P0258025F--------------------------
PORT 0258-025F - Intel Above Board
----------P02600268--------------------------
PORT 0260-0268 - LPT port address on the UniRAM card by German magazine c't
selectable from 260, 2E0, 2E8, 2F0, 3E0, 3E8.
----------P02680269--------------------------
PORT 0268-0269 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P026B------------------------------
PORT 026B - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 02ABh (default), PORT 02EBh, PORT 032Bh, PORT 036Bh
Range: PORT 03ABh, PORT 03EBh
----------P026C------------------------------
PORT 026C - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P026E026F--------------------------
PORT 026E-026F - Dell Enhanced Parallel Port
SeeAlso: PORT 002Eh,PORT 015Ch,PORT 0398h
026E -W index for data port
026F RW EPP command data
----------P0278------------------------------
PORT 0278 - Covox 'Speech Thing' COMPATIBLES
SeeAlso: PORT 022Fh"Covox",PORT 0388h-038Fh"soundmachine"
0278 -W speech data output via printer data port
(with mc-soundmachine, enabled if bit5=1 in 38F)
----------P0278027E--------------------------
PORT 0278-027E - PARALLEL PRINTER PORT (usually LPT1, sometimes LPT2)
Range: usually PORT 03BCh, PORT 0278h, or PORT 0378h
SeeAlso: MEM 0040h:0008h,INT 17/AH=00h
0278 -W data port
0279 R- status port
027A RW control port
----------P0279------------------------------
PORT 0279 - Plug-and-Play - CONFIGURATION REGISTER
SeeAlso: PORT 0A79h
0279 -W index into Plug-and-Play register set for Read Data Port and
Write Data Port I/O (see #P182,#P183)
(Table P182)
Values for Plug-and-Play Card-Level Registers:
00h set Read Port address
bits 9-2 of Read Data port address (bits 15-10 are always 0, bits 1-0
are always 11); valid Read Port addresses are 0203h-03FFh
01h serial isolation
02h configuration control
03h Wake command
(specifies which card is accessed through configuration registers)
04h resource data
05h status
06h Card Select Number (CSN)
07h logical device number
(selects which logical device on card is accessed at locations 30h-FFh)
(see #P183)
08h-1Fh reserved
20h-2Fh vendor-specific
Note: there is one set of these registers per installed card
SeeAlso: #P183
(Table P183)
Values for Plug-and-Play Logical Device Registers:
30h activate
bit 0: device is active on ISA bus
bits 7-1: reserved (0)
31h I/O range check
bit 0: I/O Read Pattern select (if bit 1 set, then I/O reads return
55h if this bit is set, AAh if this bit is clear)
bit 1: I/O Range Check Enable: if set, all reads from device I/O
registers return 55h or AAh, depending on bit 0
bits 7-2: reserved (0)
32h-37h reserved
38h-3Fh vendor-specific
40h-44h 24-bit ISA memory descriptor 0
45h-47h reserved
48h-4Ch 24-bit ISA memory descriptor 1
4Dh-4Fh reserved
50h-54h 24-bit ISA memory descriptor 2
55h-57h reserved
58h-5Ch 24-bit ISA memory descriptor 3
5Dh-5Fh reserved
60h-6Fh I/O configuration registers 0-7
70h-71h IRQ channel select 0
72h-73h IRQ channel select 1
74h-75h DMA configuration registers 0-1
76h-7Eh 32-bit memory range configuration register 0
7Fh reserved
80h-88h 32-bit memory range configuration register 1
89h-8Fh reserved
90h-98h 32-bit memory range configuration register 2
99h-9Fh reserved
A0h-A8h 32-bit memory range configuration register 3
A9h-EFh reserved for logical device configuration
F0h-FEh vendor-specific
FFh reserved
Note: there is one set of these registers per logical device
SeeAlso: #P182
----------P0280------------------------------
PORT 0280 - LCD display on Wyse 2108 PC
----------P02800288--------------------------
PORT 0280-0288 - non-standard COM port addresses (V20-XT by German magazine c't)
selectable from 0280, 0288, 0290, 0298, 6A0, 6A8
--------s-P02800283--------------------------
PORT 0280-0283 - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
----------P0288028F--------------------------
PORT 0288-028F - non-standard COM port addresses (V20-XT by German magazine c't)
0280-0288 selectable from 0280, 0288, 0290, 0298, 06A0, 06A8
0290-0298
0298-029F
--------s-P02840287--------------------------
PORT 0284-0287 - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
--------s-P0288028F--------------------------
PORT 0288-028F - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
--------s-P028C028F--------------------------
PORT 028C-028F - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
----------P02A002A7--------------------------
PORT 02A0-02A7 - Sunshine EW-901BN, EW-904BN
EPROM writer card (release 1986) for EPROMs up to 27512
02A0-02A3 adresses of the 8255 on the EW-90xBN
----------P02A202A3--------------------------
PORT 02A2-02A3 - MSM58321RS clock
----------P02A802A9--------------------------
PORT 02A8-02A9 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P02AB------------------------------
PORT 02AB - GI1904 Scanner Interface Adapter (default)
Range: PORT 022Bh, PORT 026Bh, PORT 02EBh, PORT 032Bh, PORT 036Bh
Range: PORT 03ABh, PORT 03EBh
Note: the GI1904 is used by many SPI 400/800dpi gray/halftone/color handy
scanners by Marstek, Mustek, Conrad, Völkner and others
----------P02AC------------------------------
PORT 02AC - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P02B002BF--------------------------
PORT 02B0-02BF - Trantor SCSI adapter
----------P02B002DF--------------------------
PORT 02B0-02DF - alternate EGA, primary EGA at 03C0
----------P02B802B9--------------------------
PORT 02B8-02B9 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P02C002Cx--------------------------
PORT 02C0-02Cx - AST-clock
----------P02C002DF--------------------------
PORT 02C0-02DF - XT-Real Time Clock 2 (default jumpered address)
----------P02E002E8--------------------------
PORT 02E0-02E8 - LPT port address on the UniRAM card by German magazine c't
Range: base address selectable from 0260, 02E0, 02E8, 02F0, 03E0, and 03E8.
----------P02E002EF--------------------------
PORT 02E0-02EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
(GAB 0 on XT)
02E1 ?? GPIB (adapter 0)
02E2
02E3
----------P02E002EF--------------------------
PORT 02E0-02EF - data aquisition (AT)
02E2 ?? data aquisition (adapter 0)
02E3 ?? data aquisition (adapter 0)
----------P02E8------------------------------
PORT 02E8 - S3 86C928 video controller (ELSA Winner 1000)
----------P02E802E9--------------------------
PORT 02E8-02E9 - Intel 82C212B "Neat" chipset - EMS emulation control
Range: base address may be set to 0208, 0218, 0258, 0268, 02A8, 02B8, or 02E8
----------P02E802EF--------------------------
PORT 02E8-02EF - serial port, same as 02F8, 03E8 and 03F8 (COM4)
----------P02E802EF--------------------------
PORT 02E8-02EF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
02E8 R- display status
02E8 -W horizontal total
02EA RW Lookup: DAC mask
02EB -W Lookup: DAC read index
02EC -W Lookup: DAC write index
02ED RW Lookup: DAC data
----------P02EA------------------------------
PORT 02EA - S3 86C928 video controller (ELSA Winner 1000)
----------P02EB------------------------------
PORT 02EB - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 026Bh, PORT 02ABh (default), PORT 032Bh, PORT 036Bh,
PORT 03ABh, PORT 03EBh
----------P02EC------------------------------
PORT 02EC - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P02F002F8--------------------------
PORT 02F0-02F8 - LPT port address on the UniRAM card by German magazine c't
selectable from 260, 2E0, 2E8, 2F0, 3E0, 3E8.
----------P02F802FF--------------------------
PORT 02F8-02FF - serial port, same as 02E8, 03E8 and 03F8 (COM2)
02F8 -W transmitter holding register
02F8 R- receiver buffer register
02F8 RW divisor latch, low byte when DLAB=1
02F9 RW divisor latch, high byte when DLAB=1
02F9 RW interrupt enable register when DLAB=0
02FA R- interrupt identification register
02FB RW line control register
02FC RW modem control register
02FD R- line status register
02FF RW scratch register
----------P0300------------------------------
PORT 0300 - Award POST Diagnostic
SeeAlso: PORT 0080h
--------d-P0300------------------------------
PORT 0300 - Digidesign 'Session 8' HARD-DISK RECORDING SYSTEM
SeeAlso: PORT 0200h"Digidesign"
--------s-P03000301--------------------------
PORT 0300-0301 - MPU-401 MIDI UART
Range: alternate address at PORT 0330h, occasionally at PORT 0310h or
PORT 0320h
----------P03000301--------------------------
PORT 0300-0301 - Soundblaster 16 ASP MPU-Midi EMULATION
----------P0300????--------------------------
PORT 0300-???? - HP IEC/HP-IB adapter (e.g. for use with tape streamer HP9142)
----------P03000303--------------------------
PORT 0300-0303 - Panasonic 52x CD-ROM SCSI Miniport
Range: PORT 0300h-0303h,PORT 0320h-0323h,PORT 0340h-0343h,PORT 0360h-0363h,
and PORT 0380h-0383h
----------P0300030F--------------------------
PORT 0300-030F - Philips CD-ROM player CM50
----------P0300030F--------------------------
PORT 0300-030F - CompaQ Tape drive adapter. alternate address at 0100
--------N-P0300031F--------------------------
PORT 0300-031F - 3com Ethernet adapters (default address)
--------N-P0300031F--------------------------
PORT 0300-031F - NE2000 compatible Ethernet adapters
Range: may be placed at 0300h, 0320h, 0340h, or 0360h
SeeAlso: PORT 0300h"PCnet"
--------N-P0300031F--------------------------
PORT 0300-031F - AMD PCnet - NE2100-compatible Ethernet adapters
Range: may be placed at 0300h, 0320h, 0340h, or 0360h, with the card's ROM
appearing at segment C800h, CC00h, D000h, or D400h, respectively
Note: for the PCnet-FAST chip, the I/O address may be read from the PCI
configuration space at offset 10h (see #0798 at INT 1A/AX=B10Ah)
SeeAlso: PORT 0300h"NE2000",#0798
0300-030F R- address PROM (used to store Ethernet address, etc.)
0310w RW Register Data Port (RDP) (see #P184,#P185)
0312w ?W Register Access Port (RAP) (selects register index for RDP and IDP)
(see #P202)
0314w ?W Reset
0316w RW ISA Bus Data Port (IDP)
0318w reserved for vendor-specific use
031A-031F reserved
(Table P184)
Values for AMD PCnet-ISA Register Data Port index:
00h "CSR0" status and control flags (see #P186)
01h "CSR1" low half of IADR (appears at PORT 0316h)
02h "CSR2" high half of IADR (appears at PORT 0317h)
03h "CSR3" interrupt masks (see #P187)
04h "CSR4" interrupt masks and status bits (see #P188)
08h-0Bh logical address filter
0Ch-0Eh physical address register
0Fh "CSR15" mode (see #P192)
4Ch "CSR76" receive descriptor ring length
4Eh "CSR78" transmit descriptor ring length
50h "CSR80" FIFO threshold / DMA burst control (see #P196)
52h "CSR82" DMA bus timer
58h "CSR88" chip ID
70h "CSR112" number of missed packets
72h "CSR114" number of receive collisions
7Ch "CSR124" BMU test register
bit 4: accept runt packets
SeeAlso: #P202,#P185
(Table P185)
Values for AMD PCnet-SCSI/PCnet-FAST Register Data Port index:
00h "CSR0" status and control flags (see #P186)
01h "CSR1" low half of IADR (appears at PORT 0316h)
02h "CSR2" high half of IADR (appears at PORT 0317h)
03h "CSR3" interrupt masks (see #P187)
04h "CSR4" interrupt masks and status bits (see #P188)
05h "CSR5" (PCnet-FAST) extended control and interrupt 1 (see #P189)
06h "CSR6" receive/transmit descriptor table lengths (see #P190)
07h "CSR7" (PCnet-FAST) extended control and interrupt 2 (see #P191)
08h-0Bh logical address filter
0Ch-0Eh physical address register
0Fh "CSR15" mode (see #P192)
10h "CSR16" alias of CSR1
11h "CSR17" alias of CSR2
12h "CSR18" low half of current receive buffer address
13h "CSR19" high half of current receive buffer address
14h "CSR20" low half of current transmit buffer address
15h "CSR21" high half of current transmit buffer address
16h "CSR22" low half of next receive buffer address
17h "CSR23" high half of next receive buffer address
18h "CSR24" low half of receive-ring base address
19h "CSR25" high half of receive-ring base address
1Ah "CSR26" low half of next receive descriptor address
1Bh "CSR27" high half of next receive descriptor address
1Ch "CSR28" low half of current receive descriptor address
1Dh "CSR29" high half of current receive descriptor address
1Eh "CSR30" low half of transmit ring base address
1Fh "CSR31" high half of transmit ring base address
20h "CSR32" low half of next transmit descriptor address
21h "CSR33" high half of next transmit descriptor address
22h "CSR34" low half of current transmit descriptor address
23h "CSR35" high half of current transmit descriptor address
24h "CSR36" low half of next next receive descriptor address
25h "CSR37" high half of next next receive descriptor address
26h "CSR38" low half of next next transmit descriptor address
27h "CSR39" high half of next next transmit descriptor address
28h "CSR40" current receive byte count (see #P193)
29h "CSR41" current receive status
2Ah "CSR42" current transmit byte count (see #P194)
2Bh "CSR43" current transmit status
2Ch "CSR44" next receive byte count (bits 11-0; bits 15-12=0)
2Dh "CSR45" next receive status
2Eh "CSR46" transmit poll time counter
2Fh "CSR47" transmit polling interval
30h "CSR48" receive poll time counter
31h "CSR49" receive polling interval
32h-39h reserved
3Ah "CSR58" software style (see #P195)
3Bh reserved
3Ch "CSR60" previous transmit descriptor address (low)
3Dh "CSR61" previous transmit descriptor address (high)
3Eh "CSR62" previous transmit byte count (bits 11-0; bits 15-12=0)
3Fh "CSR63" previous transmit status
40h "CSR64" next transmit buffer address (low)
41h "CSR65" next transmit buffer address (high)
42h "CSR66" next transmit byte count (bits 11-0; bits 15-12=0)
43h "CSR67" next transmit status
44h-47h reserved
48h "CSR72" receive ring counter
49h reserved
4Ah "CSR74" transmit ring counter
4Bh reserved
4Ch "CSR76" receive descriptor ring length
4Dh reserved
4Eh "CSR78" transmit descriptor ring length
4Fh reserved
50h "CSR80" FIFO threshold / DMA burst control (see #P196)
51h reserved
52h "CSR82" (PCnet-SCSI) DMA bus timer
(PCnet-FAST) transmit descriptor address (low)
53h reserved
54h "CSR84" DMA address register (low)
55h "CSR85" DMA address register (high)
56h "CSR86" buffer byte counter (bits 11-0; bits 15-12=0)
57h reserved
58h "CSR88" chip ID (low 16 bits) (see #P197)
59h "CSR89" chip ID (high 16 bits) (see #P197)
5Ah "CSR90" (PCnet-SCSI)
5Bh reserved
5Ch "CSR92" ring length conversion
5Dh reserved
5Eh "CSR94" (PCnet-SCSI)
5Fh-63h reserved
64h "CSR100" bus timeout
65h-6Fh reserved
70h "CSR112" number of missed packets
71h reserved
72h "CSR114" number of receive collisions
73h-79h reserved
7Ah "CSR122" advanced feature control (see #P198)
7Bh reserved
7Ch "CSR124" BMU test register (see #P199)
7Dh "CSR125" (PCnet-FAST) MAC Enhanced Configuration Control (see #P200)
7Eh-7Fh reserved
SeeAlso: #P184,#P224
Bitfields for AMD PCnet CSR0 status and control flags:
Bit(s) Description (Table P186)
15 "ERR" error; set if BABL, CERR, MISS, or MESS set
14 "BABL" network babbling control
13 "CERR" collision error
12 "MISS" missed frame
11 "MERR" memory error
10 "RINT" receive interrupt
9 "TINT" transmit interrupt
8 "IDON" initialization done
7 "INTR" interrupt flag
6 "IENA" interrupt enable
5 "RXON" recieve ON
4 "TXON" transmit ON
3 "TDMD" transmit demand
2 "STOP" stop -- disable all external activity
1 "STRT" start -- enable extrnal activity
0 "INIT" begin initialization procedure
SeeAlso: #P184,#P187
Bitfields for AMD PCnet CSR3 interrupt masks:
Bit(s) Description (Table P187)
15 reserved
14 "BABLM" disable babble interrupt
13 reserved
12 "MISSM" disable missed-frame interrupt
11 "MERM" disable memory-error interrupt
10 "RINTM" disable receive interrupt
9 "TINTM" disable transmit interrupt
8 "IDONM" disable initialization-done interrupt
7-5 reserved
4 "DXMT2PD" disable Transmit Two Part Deferral
3 "EMBA" enable modified back-off algorithm
2-0 reserved
Note: other bits are reserved
SeeAlso: #P184,#P186,#P188
Bitfields for AMD PCnet CSR4 interrupt masks and status bits:
Bit(s) Description (Table P188)
15 "ENTST" enable Test Mode / CSR124 access
14 "DMAPLUS" disable CSR80 burst transaction counter
13 "TIMER" enable Bus Timer register
12 "DPOLL" disable transmit polling
11 "APADXMT" Auto-Pad Transmit
10 "ASTRPRCV" enable automatic pad stripping
9 "MFCO" missed frame counter has overflowed
8 "MFCOM" disable interrupt on MFCO
7 "UINTCMD" (PCnet-FAST) user interrupt command
6 "UINT" (PCnet-FAST) user interrupt pending
write 1 to clear
5 "RCVCCO" receive collision counter has overflowed
4 "RCVCCOM" disable interrupt on RCVCCO
3 "TXSTRT" Transmit Start
2 "TXSTRTM" disable interrupt on TXSTRT
1 "JAB" Jabber error
0 "JABM" disable interrupt on JAB
SeeAlso: #P184,#P187,#P185
Bitfields for AMD PCnet-FAST CSR5 extended control and interrupt 1:
Bit(s) Description (Table P189)
31-16 reserved
15 "TOKINTD" disable Transmit OK interrupt
14 "LTINTEN" enable Last Transmit interrupt
13-12 reserved
11 "SINT" System Interrupt (write 1 to clear)
10 "SINTE" enable System Interrupt
9 "SLPINT" Sleep Interrupt (write 1 to clear)
8 "SLPINTE" enable Sleep Interrupt
7 "EXDINT" Excessive Deferral Interrupt (write 1 to clear)
6 "EXDINTE" enable Excessive Deferral Interrupt
5 "MPPLBA" Magic Packet Physical Logical Broadcast Accept
4 "MPINT" Magic Packet Interrupt (write 1 to clear)
3 "MPINTE" enable Magic Packet Interrupt
2 "MPEN" enable Magic Packet mode
1 "MPMODE" Magic Packet mode active
0 "SPND" Suspend
SeeAlso: #P185,#P188,#P191
Bitfields for AMD PCnet CSR6 Descriptor Table Length register:
Bit(s) Description (Table P190)
15-12 transmit encoded ring length
11-8 receive encoded ring length
7-0 reserved
SeeAlso: #P185,#P189
Bitfields for AMD PCnet CSR7 Extended Control and Interrupt 2:
Bit(s) Description (Table P191)
15 "FASTSPNDE" enable Fast Suspend
14 "RXFRTG" Receive Frame Tag
13 "RDMD" Receive Demand
12 "RXDPOL" disable receive polling
11 "STINT" Software Timer Interrupt (write 1 to clear)
10 "STINTE" enable Software Timer Interrupt
9 "MREINT" MII Management Read Error Interrupt (write 1 to clear)
8 "MREINTE" enable MII Management Read Error Interrupt
7 "MAPINT" MII Management Auto-Poll Interrupt (write 1 to clear)
6 "MAPINTE" enable MII Management Auto-Poll Interrupt
5 "MCCINT" MII Management Command Complete Interrupt (write 1 to clr)
4 "MCCINTE" enable MII Management Command Complete Interrupt
3 "MCCIINT" MII Management Command Complete Internal Interrupt
(write 1 to clear)
2 "MCCIINTE" enable MII Manamagement Command Complete Internal Int.
1 "MIIPDTINT" MII PHY Detect Transition Interrupt (write 1 to clear)
0 "MIIPDTINTE" enable MII PHY Detect Transition Interrupt
SeeAlso: #P185,#P189
Bitfields for AMD PCnet CSR15 mode flags:
Bit(s) Description (Table P192)
15 "PROM" promiscuous mode
14 "DRCVBC" disable Receive Broadcast
13 "DRCVPA" disable Receive Physical Address
12 "DLNKTST" disable Link Status
11 "DAPC" disable Automatic Polarity Correction
10 "MENDECL" MENDEC loopback mode
9 "LRT/TSEL" Low Receive Threshold
8-7 "PORTSEL" Port Select
00 AUI
01 10Base-T
10 GPSI
11 reserved
6 "INTL" internal loopback
5 "DRTY" disable retry
4 "FCOLL" force collision
3 "DXMTFCS" disable Transmit CRC
2 "LOOP" enable Loopback
1 "DTX" disable transmitter
0 "DRX" disable receiver
SeeAlso: #P184,#P188,#P196
Bitfields for AMD PCnet CSR40 Current Receive Byte Count register:
Bit(s) Description (Table P193)
15-12 reserved (0)
11-0 current receive byte count (copy of BCNT field of current receive
descriptor's RMD1)
SeeAlso: #P185,#P194
Bitfields for AMD PCnet CSR42 Current Transmit Byte Count register:
Bit(s) Description (Table P194)
15-12 reserved (0)
11-0 current transmit byte count (copy of BCNT field of current receive
descriptor's TMD1)
SeeAlso: #P185,#P193
Bitfields for AMD PCnet CSR58 Software Style register:
Bit(s) Description (Table P195)
15-11 reserved (undefined)
10 "APERREN" enabled advanced parity error handling
9 "CSRPCNET" PCnet-ISA compatibility (read-only)
8 "SSIZE32" 32-bit software structures for data blocks
7-0 "SWSTYLE" software style
00h LANCE/PCnet-ISA (16-bit software structures)
01h reserved
02h PCnet-PCI (32-bit software)
03h PCnet-PCI (32-bit software)
SeeAlso: #P185
Bitfields for AMD PCnet CSR80 FIFO threshold and DMA burst control:
Bit(s) Description (Table P196)
15-14 reserved
13-12 receive FIFO high-water mark; request DMA when N byte available
00 = 16 bytes
01 = 32 bytes
10 = 64 bytes
11-10 transmit starting point; start transmission after N bytes written
00 = 4 bytes
01 = 16 bytes
10 = 64 bytes
11 = 112 bytes
9-8 transmit FIFO low-water mark; start DMA when room for N bytes
00 = 8 bytes
01 = 16 bytes
10 = 32 bytes
7-0 DMA burst register
SeeAlso: #P184,#P192
Bitfields for AMD PCnet Chip ID register (read-only):
Bit(s) Description (Table P197)
31-28 hardware version
27-12 part number
2623h = Am79C971
11-1 manufacturer ID (0001h = AMD)
0 reserved (1)
SeeAlso: #P185
Bitfields for AMD PCnet CSR122 Advanced Feature Control register:
Bit(s) Description (Table P198)
15-1 reserved
0 "RCVALGN" DWORD-align received packets
SeeAlso: #P185,#P199
Bitfields for AMD PCnet CSR124 Test Register 1:
Bit(s) Description (Table P199)
15-5 reserved
4 (PCnet-SCSI) accept runt packets
3 (PCnet-FAST) accept runt packets
2-0 reserved
SeeAlso: #P185,#P198
Bitfields for AMD PCnet-FAST CSR125 MAC Enhanced Configuration Control reg:
Bit(s) Description (Table P200)
15-8 inter-packet gap (reducing from default 96 can disrupt network)
7-0 inter-frame spacing, part 1
SeeAlso: #P185
(Table P201)
Values for AMD PCnet-ISA ISA Bus Configuration Register index:
00h "MSRDA" width of DMA read signal
01h "MSWRA" width of DMA write signal
02h "MC" ISA bus configuration (see #P204)
05h "LED1" LED1 signal control (see #P205)
06h "LED2" LED2 signal control (see #P205)
07h "LED3" LED3 signal control (see #P205)
SeeAlso: #P184,#P224,#P202
(Table P202)
Values for AMD PCnet-SCSI Bus Configuration Register index:
00h "MSRDA" width of DMA read signal (reserved)
01h "MSWRA" width of DMA write signal (reserved)
02h "MC" miscellaneous configuration (see #P204)
03h reserved
04h "LINKST" link status
05h "LED1" LED1 signal control (see #P205) -- receive status
06h "LED2" LED2 signal control (see #P205)
07h "LED3" LED3 signal control (see #P205) -- transmit status
08h-0Fh reserved
10h "IOBASEL"
11h "IOBASEU"
12h "BSBC" burst size and bus control
13h "EECAS" EEPROM Control and Status
14h "SWS" software style
15h "INTCON" reserved
SeeAlso: #P185,#P201,#P203
(Table P203)
Values for AMD PCnet-FAST Bus Configuration Register index:
00h "MSRDA" width of DMA read signal (reserved)
01h "MSWRA" width of DMA write signal (reserved)
02h "MC" miscellaneous configuration (see #P204)
03h reserved !!!p.154
04h "LED0" LED0 status
05h "LED1" LED1 signal control (see #P205) -- receive status
06h "LED2" LED2 signal control (see #P205)
07h "LED3" LED3 signal control (see #P205) -- transmit status
08h reserved
09h "FDC" full-duplex control
0Ah-0Fh reserved
10h "IOBASEL" I/O base select (lo) -- reserved
11h "IOBASEU" I/O base select (hi) -- reserved
12h "BSBC" burst size and bus control
13h "EECAS" EEPROM Control and Status
14h "SWS" software style
15h "INTCON" reserved
16h "PCILAT" PCI-bus latency
17h "PCISID" PCI subsystem ID
18h "PCISVID" PCI subsystem vendor ID
19h "SRAMSIZ" SRAM size
1Ah "SRAMB" SRAM boundary
1Bh "SRAMIC" SRAM interface control
1Ch "EBADDRL" expansion bus address (low)
1Dh "EBADDRU" expansion bus address (high)
1Eh "EBD" expansion bus data port
1Fh "STVAL" software timer value
20h "MIICAS" MII control and status
21h "MIIADDR" MII address
22h "MIIMDR" MII management data
23h "PCIVID" PCI vendor ID
SeeAlso: #P185,#P201,#P202
Bitfields for AMD PCnet ISA bus configuration:
Bit(s) Description (Table P204)
3 EADISEL
2 AWAKE
1 ASEL
0 XMAUSEL
SeeAlso: #P202,#P205
Bitfields for AMD PCnet LEDn signal control:
Bit(s) Description (Table P205)
15 LEDOUT
14-8 reserved
7 PSE
6-5 reserved
4 XMTE
3 RVPE
2 RCVE
1 JABE
0 COLE
SeeAlso: #P202
----------P0300031F--------------------------
PORT 0300-031F - prototype cards
Periscope hardware debugger
----------P030C030F--------------------------
PORT 030C-030F - AIMS LAB PC Radio
Range: configurable to PORT 020Ch or PORT 030Ch
Notes: writing a value with bit 3 set to one of these ports turns on the
radio; writing a value with bit 3 clear turns it off
PORT 020Eh bits 1 indicates status of some kind
--------s-P03100311--------------------------
PORT 0310-0311 - MPU-401 MIDI UART
Range: alternate address at PORT 0300h or PORT 0330h, occasionally at
PORT 0320h
----------P0310031F--------------------------
PORT 0310-031F - Philips CD-ROM player CM50
--------s-P03200321--------------------------
PORT 0320-0321 - MPU-401 MIDI UART
Range: alternate address at PORT 0300h or PORT 0330h, occasionally at
PORT 0310h
----------P03200323--------------------------
PORT 0320-0323 - XT HDC 1 (Hard Disk Controller)
SeeAlso: PORT 01F0h-01F7h
0320 RW data register
0321 -W reset controller
0321 R- read controller hardware status (see #P206)
0322 R- read DIPswitch setting on XT controller card
0322 -W generate controller-select pulse
0323 -W write pattern to DMA and INT mask register
Bitfields for XT hard disk controller hardware status:
Bit(s) Description (Table P206)
7-6 always 0
5 logical unit number
4-2 always 0
1 error occurred
0 always 0
----------P03240327--------------------------
PORT 0324-0327 - XT HDC 2 (Hard Disk Controller)
----------P0328032B--------------------------
PORT 0328-032B - XT HDC 3 (Hard Disk Controller)
----------P032B------------------------------
PORT 032B - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 026Bh, PORT 02ABh (default), PORT 02EBh, PORT 036Bh,
PORT 03ABh, PORT 03EBh
----------P032C------------------------------
PORT 032C - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P032C032F--------------------------
PORT 032C-032F - XT HDC 4 (Hard Disk Controller)
----------P03300331--------------------------
PORT 0330-0331 - MPU-401 MIDI UART
Range: alternate address at PORT 0300h, occasionally at PORT 0310h or
PORT 0320h
0330 RW data register
0331 R- status register (see #P207)
0331 -W command register (see #P208)
Note: MPU-401 genarates an interrupt when MIDI code is ready; by reading
MIDI code from the data register this interrupt is cleared
Bitfields for MPU-401 status register:
Bit(s) Description (Table P207)
7 input ready
=1 no data is available for reading
=0 data is available for reading
6 output ready
=1 not ready to receive command/data byte
=0 ready to receive command/data byte
5-0 reserved
Note: pending input seems to block the output
SeeAlso: #P208
(Table P208)
Values for MPU-401 commands (data go to/from PORT 0330h):
Command Description Results Parameter
01h send MIDI stop ACK -
02h send MIDI start ACK -
03h send MIDI continue ACK -
15h stop all (recording, ACK -
playback and MIDI)
34h return timing bytes ACK -
in stop mode
35h enable mode messages ACK -
to PC
38h enable system common ACK -
messages to PC
39h enable real time ACK -
messages to PC
3Ch use CLS sync ACK -
3Dh use SMPTE sync ACK -
3Fh enter UART mode ACK -
80h use MIDI sync ACK -
81h use FSK sync ACK -
82h use MIDI sync ACK -
83h enable metronome ACK -
84h disable metronome ACK -
87h enable pitch and ACK -
controller
8Ah disable data in stopped ACK -
mode
8Bh enable data in stop mode ACK -
8Ch disable measure end ACK -
messages to host
91h enable ext MIDI control ACK -
94h disable clock to host ACK -
95h enable clock to host ACK -
97h enable system exclusive ACK -
messages to PC
ACh get MIDI version ACK,VER -
ADh get revision ACK,REV -
Cxh set timebase to x*24 ACK -
ppqn (x>1)
D0h ??? ACK -
DFh ??? ACK -
E0h set tempo ACK BPS
E4h set clocks per click ACK CPC
E6h set beats per measure ACK BPM
E7h send all clocks to host ACK 1 byte
(04h is sent)
FFh reset ACK -
Notes: after receiving a command byte MPU-401 must reply with command
acknowledge byte FEh in data register
command parameters are sent, and response bytes are received through
the data register
no commands (except reset) can be issued in UART mode, and MPU-401
must be reset to leave UART mode
Key:
ACK command acknowledge byte (FEh)
VER MIDI version number
bits 7-4: major version
bits 0-3: minor version
REV revision number
BPS beats per second (8..250)
CPC clocks per click
BPM beats per measure
SeeAlso: #P208
----------P03300333--------------------------
PORT 0330-0333 - Adaptec 154xB/154xC SCSI adapter (default address)
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
Note: BusLogic BT-545S and DTC 3290 seem to be "almost" compatible with
the Adaptec AHA-154x
0330 R- status register (see #P209)
0330 -W control register (see #P210)
0331 R- data in register
0331 -W command / data out register (see #P212)
0332 R- interrupt status register (see #P211)
Bitfields for AHA-154x status register:
Bit(s) Description (Table P209)
7 self-test in progress (STST)
6 diagnostic failure (DIAGF)
5 mailbox initialization required (INIT)
4 adapter idle (IDLE)
3 command register full (CDF)
2 data register full (DF)
1 reserved
0 invalid command (INVDCMD)
Note: data in register should only be read if bit 2 is set
command / data out register should only be written if bit 3 is zero
SeeAlso: #P210,#P211,#P212
Bitfields for AHA-154x control register:
Bit(s) Description (Table P210)
7 hardware reset (HRST)
6 software reset (SRST)
5 interrupt reset (IRST)
4 SCSI bus reset (SCRST)
0-3 reserved
SeeAlso: #P209
Bitfields for AHA-154x interrupt status register:
Bit(s) Description (Table P211)
7 any interrupt (ANYINTR)
4-6 reserved
3 SCSI reset detected (SCRD)
2 host adapter command complete (HACC)
1 mailbox out available (MBOA)
0 mailbox in full (MBIF)
SeeAlso: #P209
(Table P212)
Values for AHA-154x host adapter commands:
Command Description Parameters Results
00h no operation - -
01h mailbox initializa- NMB,MBA0,MBA1,MBA2 -
tion
02h start SCSI command - -
03h start BIOS command BFN,TRG,CH,CLHH,HL,SN,SC, -
BA0,BA1,BA2
04h adapter inquiry - BT,SOID,RC0,RC1
05h enable mailbox out 1 byte -
interrupt
06h set selection 4 bytes -
timeout
07h set bus on time BON -
08h set bus off time BOFF -
09h set AT bus transfer ATBS -
speed
0Ah return installed - ID0,ID1,ID2,ID3,
devices ID4,ID5,ID6,ID7
0Bh return configuration - DRQ,IRQ,SID
data
0Ch enable target mode 2 bytes -
0Dh return setup data NSD OPT,ATBS,
BON,BOFF,
NMB,MBA0,MBA1,MBA2,
S0,S1,S2,S3,S4,S5,S6,S7,
DS
1Ah write channel 2 3 bytes -
buffer
1Bh read channel 2 3 bytes -
buffer
1Ch write FIFO buffer 3 bytes -
1Dh read FIFO buffer 3 bytes -
1Fh echo command data D D
20h run adapter - -
diagnostics
21h set adapter options ESG,DS -
22h program EEPROM 35 bytes -
(AHA-1542C)
23h return EEPROM data ???,NED,EA EEPROM data
(AHA-1542C) bytes
24h set shadow RAM 1 byte -
parameters
(AHA-1542C???)
25h BIOS mailbox NMB,MBA0,MBA1,MBA2 -
initialization
(since AHA-1540B
rev. 1.4???)
26h set BIOS bank 1 - -
(AHA-1542C???)
27h set BIOS bank 2 - -
(AHA-1542C???)
28h return extended BIOS - F,MBLC
information (since
AHA-1540B rev.
1.4???)
29h enable mailbox EMB,MBLC -
interface (since
AHA-1540B rev.
1.4???)
82h start BIOS SCSI - -
command (since
AHA-1540B rev.
1.4???)
Note: NMB number of "in" and "out" mailboxes
MBA0..MBA2 MSB..LSB of the physical address of the array of mailboxes
(see #P213)
BFN BIOS function number
TRG bits 7-5: target ID
bits 4-0: reserved
CH bits 7-4: reserved
bits 3-0: bits 9-6 of cylinder number
CLHH bits 7-2: bits 5-0 of cylinder number
bits 1-0: bits 5-4 of head number
HL bits 7-4: reserved
bits 3-0: bits 3-0 of head number
SN sector number - 1
SC sector count
BA0..BA2 MSB..LSB of the physical address of data buffer
BT board type
20h BusLogic BT-545S
31h Adaptec AHA-1540
41h Adaptec AHA-1540A/1542A/1542B
42h Adaptec AHA-1640
43h Adaptec AHA-1542C
44h Adaptec AHA-1542CF
45h=Adaptec AHA-1542CF with BIOS v2.01
SOID special options ID
30h ???
41h standard model
RC0/RC1 alphanumeric revision code
BON bus on time (time in microseconds adapter stays on the AT
bus when transferring data: 2..15, default is 11)
BOFF bus off time (time in microseconds adapter stays off the AT
bus when transferring data: 1..64, default is 4)
ATBS AT bus transfer speed
00h,AAh 5.0 MB/s
01h,99h 6.7 Mb/s
02h 8.0 Mb/s
03h,88h 10.0 Mb/s
04h 5.7 Mb/s
BBh 4.0 Mb/s???
CCh 3.3 Mb/s???
DDh 2.9 Mb/s???
EEh 2.5 Mb/s???
FFh 2.2 Mb/s???
ID0..ID7 bit m in byte IDn is set if SCSI ID n LUN m is online
DRQ DRQ select
bit 7: DRQ7
bit 6: DRQ6
bit 5: DRQ5
bit 4-1: reserved
bit 0: DRQ0
IRQ IRQ select
bit 7: reserved
bit 6: IRQ15
bit 5: IRQ14
bit 4: IRQ13
bit 3: IRQ12
bit 2: IRQ11
bit 1: IRQ10
bit 0: IRQ9
SID host adapter SCSI ID
NSD number of setup data bytes to return
OPT options
bit 0: synchronous negotiation
bit 1: SCSI parity
S0..S7 synchronous transfer timings for target IDs 0..7
each byte laid out as follows
bit 7: synchronous timing valid
bits 6-4: synchronous transfer period
bits 3-0: synchronous offset
DS disconnect status
bit n is set if target ID n is unable to disconnect???
D any data byte (it must be echoed back)
ESG enable scatter/gather???
NED number of EEPROM data bytes to return
EA EEPROM address to read data from
F flags
bit 3: extended BIOS enabled
MBLC mailbox lock code
bit 0: BIOS uses 256 heads 63 sectors LBA to CHS
translation???
EMB 0 to enable mailbox interface???
Note: all commands except 01h, 02h should only be issued if the host adapter
is idle (bit 4 in PORT 0330h set)
command 02h can be issued even if the command / data out register is
full (bit 3 in PORT 0330h may be set)
command 02h causes host adapter to scan both its SCSI and BIOS
mailboxes; command 82h causes host adapter to scan its BIOS mailboxes
all host adapter commands except 02h cause host adapter command
complete interrupt (bit 2 in PORT 332h) after their completetion
return setup data command (0Dh) returns the number of bytes requested
with NSD parameter
BusLogic BT-545S gets the adapter inquiry command (04h) wrong returning
only one byte instead of four; DTC 3290 gets this command wrong too
SeeAlso: #P209,#P211
Format of AHA-154x mailbox array:
Offset Size Description (Table P213)
00h N*4 BYTEs array of N "out" mailboxes (see #P214)
N*4 N*4 BYTEs array of N "in" mailboxes (see #P214)
Notes: the "out" mailboxes are scanned by the host adapter in a round-robin
fashion, i.e. the host adapter first looks into an "out" mailbox
which follows one least recently used (and wraps around if it was
the last one in the array
array of "in" mailboxes is absent in the case of BIOS mailboxes
SeeAlso: #P209,#P215,#P216
Format of AHA-154x mailbox:
Offset Size Description (Table P214)
00h BYTE mailbox command/status code (see #P215,#P216)
01h 3 BYTEs address of the command control block (CCB) (see #P217)
physical address in big-endian format
SeeAlso: #P209,#P213
(Table P215)
Values for mailbox out command codes:
00h CCB is free
01h start CCB
02h abort CCB
SeeAlso: #P209,#P213,#P216
(Table P216)
Values for mailbox in status codes:
00h command in progress
01h CCB completed
02h CCB aborted
03h CCB abort failed
04h CCB completed with error
SeeAlso: #P209,#P213,#P215
Format of AHA-154x command control block (CCB):
Offset Size Description (Table P217)
00h BYTE CCB operation code (see #P218)
01h BYTE address and control
bits 5-7: target/initiator ID
bit 4: outbound data
bit 3: inbound data
bits 0-2: LUN
02h BYTE SCSI command length
03h BYTE request sense allocation length
write 0 to disable auto-sense
04h 3 BYTEs data length
in big-endian format
07h 3 BYTEs data pointer
physical address in big-endian format
0Ah 3 BYTEs link pointer (link to the next CCB for linked commands)
physical address in big-endian format
0Dh BYTE command linking ID (for linked commands)
mailbox status code (if this is a CCB in a BIOS mailbox,
see #P216)
0Eh BYTE host adapter status (see #P219)
0Fh BYTE target device status
SCSI status byte
10h 2 BYTEs reserved
12h N BYTEs SCSI command descriptor block (CDB)
12h+N M BYTEs auto-sense data
SeeAlso: #P209
(Table P218)
Values for CCB type:
00h initiator CCB
01h target CCB
02h initiator CCB with scatter/gather (see #P220)
03h initiator CCB with residual length
04h initiator CCB with scatter/gather and residual length (see #P220)
81h bus device reset CCB
Note: residual length is returned in the data length field of CCB
initiator CCB with scatter/gather cannot have a zero data length
SeeAlso: #P209
(Table P219)
Values for host adapter status:
00h command complete
0Ah linked command complete (linked CCBs only)
0Bh linked command complete with flag (linked CCBs only)
11h selection time out
12h data overrun/underrun
13h unexpected bus free
14h target bus phase sequence failure
15h invalid mailbox out command
16h invalid CCB operation code
17h linked CCB does not have the same LUN
18h invalid target direction received from host (target mode only)
19h dupilcate CCB received in target mode
1Ah invalid CCB or segment list parameter
Note: in the case of target bus sequence failure host adapter will generate
a SCSI reset condition, notifying the host with a SCRD interrupt
SeeAlso: #P209
Format of AHA-154x scatter/gather segment:
Offset Size Description (Table P220)
00h 3 BYTEs data length
in big-endian format
03h 3 BYTEs data pointer
physical address in big-endian format
SeeAlso: #P209
----------P0330033F--------------------------
PORT 0330-033F - CompaQ SCSI adapter. alternate address at 0130
----------P0330033F--------------------------
PORT 0330-033F - Philips CD-ROM player CM50
----------P03340337--------------------------
PORT 0334-0337 - Adaptec 154xB/154xC SCSI adapter.
Range: four ports at any of 0130, 0134, 0230, 0234, 0330 (default) or 0334
----------P0338------------------------------
PORT 0338 - AdLib soundblaster card
----------P0338033F--------------------------
PORT 0338-033F - COM port addresses on UniRAM card by German magazine c't
Range: selectable from 0238, 02E8, 02F8, 0338, 03E0, 03E8, 03F8
----------P0340034F--------------------------
PORT 0340-034F - Philips CD-ROM player CM50
----------P0340034F--------------------------
PORT 0340-034F - SCSI (1st Small Computer System Interface) adapter
Range: alternate address at 0140-014F
----------P0340034F--------------------------
PORT 0340-034F - Gravis Ultra Sound by Advanced Gravis
Range: The I/O address range is dipswitch selectable from:
0200-020F and 0300-030F
0210-021F and 0310-031F
0220-022F and 0320-032F
0230-023F and 0330-033F
0240-024F and 0340-034F
0250-025F and 0350-035F
0260-026F and 0360-036F
0270-027F and 0370-037F
Note: the AMD InterWave chip provides a superset of the UltraSound's
functionality, including these ports
SeeAlso: PORT 0240h-024Fh,PORT 0746h
0340 -W MIDI Control (see #P221)
0340 R- MIDI Status (see #P222)
0341 -W MIDI Transmit Data
0341 R- MIDI Receive Data
0342 RW GF1 Page Register / Voice Select
0343 RW GF1/Global Register Select (see #P223)
0344 RW GF1/Global Data Low Byte (16 bits)
0345 RW GF1/Global Data High Byte (8 bits)
0346 -W Mixer Data Port
0347 RW GF1 DRAM
Direct Read Write at Loction pointed with regs 43 and 44
Bitfields for Gravis Ultra Sound MIDI control register:
Bit(s) Description (Table P221)
7 Receive IRQ (1 = enabled)
5-6 Xmit IRQ
0-1 Master Reset (1 = enabled)
SeeAlso: #P178,#P180,#P222
Bitfields for Gravis Ultra Sound MIDI status register:
Bit(s) Description (Table P222)
7 Interrupt pending
5 Overrun Error
4 Framing Error
1 Transmit Register Empty
0 Receive Register Empty
SeeAlso: #P221,#P223
(Table P223)
Values for Gravis Ultra Sound GF1/Global Registers:
---Voice specific registers---
00h w Voice Control (see #P225)
01h w Frequency Control
bit 15-10 Integer Portion
bit 9-1 Fractional Portion
02h w Start Address HIGH
bit 12-0 Address Lines 19-7
03h w Start Address LOW
bit 15-9 Address Lines 6-0
bit 8-5 Fractional Part of Start Address
04h w End Address HIGH
bit 12-0 Address Lines 19-7
05h w End Address LOW
bit 15-9 Address Lines 6-0
bit 8-5 Fractional Part of End Address
06h w Volume Ramp Rate
bit 5-0 Amount added
bit 7-6 Rate
07h w Volume Ramp Start
bit 7-4 Exponent
bit 3-0 Mantissa
08h w Volume Ramp End
bit 7-4 Exponent
bit 3-0 Mantissa
09h w Current Volume
bit 15-12 Exponent
bit 11-4 Mantissa
0Ah w Current Address HIGH
bit 12-0 Address Lines 19-7
0Bh w Current Address LOW
bit 15-9 Address Lines 6-0
bit 8-0 Fractional Position
0Ch w Pan Position
bit 3-0 Pan Postion
0Dh w Volume Control (see #P226)
0Eh w Active Voices
bit 5-0 #Voices -1 (allowed 13 - 31)
0Fh w IRQ Source Register (see #P227)
---NOT voice specific---
41h r/w DRAM DMA Control (see #P228)
42h w DMA Start Address
bits 15-0 DMA Address Lines 19-4
43h w DRAM I/O Address LOW
44h w DRAM I/O Address HIGH
bits 0-3 Upper 4 Address Lines
45h r/w Timer Control
bit 3 Enable Timer 2
bit 2 Enable Timer 1
46h w Timer 1 Count (granularity of 80 micro sec)
47h w Timer 2 Count (granulatity of 320 micro sec)
48h w Sampling Frequency
rate = 9878400 / (16 * (FREQ + 2))
49h r/w Sampling Control (see #P229)
4Bh w Joystick Trim DAC
4Ch r/w RESET
bit 2 GF1 Master IRQ Enable
bit 1 DAC Enable
bit 0 Master Reset
---Voice specific registers---
80h r Voice Control (see 00h)
81h r Frequency Control (see 01h)
82h r Start Address HIGH (see 02h)
83h r Start Address LOW (see 03h)
84h r End Address HIGH (see 04h)
85h r End Address LOW (see 05h)
86h r Volume Ramp Rate (see 06h)
87h r Volume Ramp Start (see 07h)
88h r Volume Ramp End (see 08h)
89h r Current Volume (see 09h)
8Ah r Current Address HIGH (see 0Ah)
8Bh r Current Address LOW (see 0Bh)
8Ch r Pan Position (see 0Ch)
8Dh r Volume Control (see 0Dh)
8Eh r Active Voices (see 0Eh)
8Fh r IRQ Status (see 0Fh)
SeeAlso: #P222,#P224
(Table P224)
Values for InterWave synthesizer registers:
---voice-specific registers---
10h w synthesizer upper address
11h w synthesizer effects address high (16 bits)
12h w synthesizer effects address low (16 bits)
13h w synthesizer left offset (16 bits)
14h w synthesizer effects output accumulator select
15h w synthesizer mode select
16h w synthesizer effects volume (16 bits)
17h w synthesizer frequency LFO
18h w synthesizer volume LFO
---NOT voice-specific---
19h w synthesizer global mode
1Ah w synthesizer LFO base address (16 bits)
---voice-specific registers---
1Bh w synthesizer right offset (16 bits)
1Ch w synthesizer left offset (16 bits)
1Dh w synthesizer effect volume final (16 bits)
---NOT voice-specific---
41h r/w local memory control: DMA control
42h r/w local memory control: DMA start address bits 19-4 (16 bits)
43h w local memory control: I/O address low (16 bits)
44h w local memory control: I/O address high (16 bits)
45h r/w AdLib/SoundBlaster control
46h r/w AdLib timer 1
47h r/w AdLib timer 2
49h r/w ADC sample control
4Bh r/w joystick trim
4Ch w GUS reset
50h r/w local memory control: DMA start address bits 23-20/3-0 (16 bits)
51h r/w local memory control: 16-bit access
52h r/w local memory control: configuration
53h r/w local memory control: control
54h r/w local memory control: record FIFO base address bits 23-8 (16-bit)
55h r/w local memory control: playback FIFO base address bits 23-8 (16-bit)
56h r/w local memory control: FIFO size (16-bit)
57h r/w local memory control: DMA interleave control (16-bit)
58h r/w local memory control: DMA interleaev base address bits 23-8
59h r/w compatibility control
5Ah r/w decode control
5Bh r/w version number
5Ch r/w MPU-401 emulation control A
5Dh r/w MPU-401 emulation control B
5Eh w MIDI receive FIFO access
5Fh - reserved
60h r/w emulation IRQ
---voice-specific registers---
90h r synthesizer upper address
91h r synthesizer effects address high (16 bits)
92h r synthesizer effects address low (16 bits)
93h r synthesizer left offset (16 bits)
94h r synthesizer effects output accumulator select
95h r synthesizer mode select
96h r synthesizer effects volume (16 bits)
97h r synthesizer frequency LFO
98h r synthesizer volume LFO
---NOT voice-specific---
99h r synthesizer global mode
9Ah r synthesizer LFO base address (16 bits)
---voice-specific registers---
9Bh r synthesizer right offset (16 bits)
9Ch r synthesizer left offset (16 bits)
9Dh r synthesizer effect volume final (16 bits)
---NOT voice-specific---
9Fh r synthesizer voices IRQ
Note: these registers are *in*addition* to the Gravis UltraSound registers
SeeAlso: #P223
Bitfields for Gravis Ultra Sound voice control global register:
Bit(s) Description (Table P225)
7 IRQ pending
6 Direction
5 Enable WAVE IRQ
4 Enable bi-directional Looping
3 Enable Looping
2 Size data (8/16 bits)
1 Stop Voice
0 Voice Stopped
SeeAlso: #P223,#P226
Bitfields for Gravis Ultra Sound volume control global register:
Bit(s) Description (Table P226)
7 IRQ Pending
6 Direction
5 Enable Volume Ramp IRQ
4 Enable bi-directional Looping
3 Enable Looping
2 Rollover Condition
1 Stop Ramp
0 Ramp Stopped
SeeAlso: #P223,#P225
Bitfields for Gravis Ultra Sound IRQ source register:
Bit(s) Description (Table P227)
7 WaveTable IRQ pending
6 Volume Ramp IRQ pending
4-0 Voice Number
SeeAlso: #P223,#P225,#P228
Bitfields for Gravis Ultra Sound DRAM DMA control register:
Bit(s) Description (Table P228)
7 Invert MSB
6 Data Size (8/16 bits)
5 DMA Pending
3-4 DMA Rate Divider
2 DMA Channel Width (8/16 bits)
1 DMA Direction (1 = read)
0 DMA Enable
SeeAlso: #P223,#P227
Bitfields for Gravis Ultra Sound sampling control register:
Bit(s) Description (Table P229)
7 Invert MSB
6 DMA IRQ pending
5 DMA IRQ enable
2 DMA width (8/16 bits)
1 Mode (mone/stereo)
0 Start Sampling
SeeAlso: #P223
----------P03400357--------------------------
PORT 0340-0357 - RTC (1st Real Time Clock for XT)
(used by TIMER.COM v1.2 which is the 'standard' timer program)
Range: alternate at 0240-0257
SeeAlso: PORT 0240h-0257h
0340 RW 0.001 seconds 0-99
0341 RW 0.1 and 0.01 seconds 0-99
0342 RW seconds 0-59
0343 RW minutes 0-59
0343 RW hours 0-23
0345 RW day of week 1-7
0346 RW day of month 1-31
0347 RW month 1-12
0348 RW RAM (upper nybble only)
0349 RW year 0-99
034A RW RAM last month storage
034B RW RAM year storage (-80)
034C RW RAM reserved
034D RW RAM not used
034E RW RAM not used
034F RW RAM not used
0350 R- interrupt status register
0351 -W interrupt control register
0352 -W counter reset
0353 -W RAM reset
0354 R- status bit
0355 -W GO command
0356 ?? standby interrupt
0357 ?? test mode
----------P03480357--------------------------
PORT 0348-0357 - DCA 3278
----------P034C034F--------------------------
PORT 034C-034F - Gravis UltraMax by Advanced Gravis
Range: The I/O address range is dipswitch selectable from:
0200-020F and 0300-030F
0210-021F and 0310-031F
0220-022F and 0320-032F
0230-023F and 0330-033F
0240-024F and 0340-034F
0250-025F and 0350-035F
0260-026F and 0360-036F
0270-027F and 0370-037F
----------P035A035B--------------------------
PORT 035A-035B - Adaptec AH1520 jumper settings
035A R I/O channel setup (see #P230)
035B R transfer mode setup (see #P231)
Bitfields for Adaptec AH1520 channel setup jumper settings:
Bit(s) Description (Table P230)
7 SCSI parity disabled
6-5 DMA channel (00 = channel 0, 01 = 5, 10 = 6, 11 = 7)
4-3 IRQ number (00 = IRQ9, 01 = IRQ10, 10 = IRQ11, 11 = IRQ12)
2-0 SCSI ID
SeeAlso: #P231
Bitfields for Adaptec AH1520 transfer mode setup jumper settings:
Bit(s) Description (Table P231)
7 DMA transfer mode (clear for PIO)
6 boot enabled
5-4 boot type
00 ???
01 boot from floppy
10 print configured options
11 boot from hard disk
3 enable sync negotiation
2 enable target disconnection
1-0 unused???
SeeAlso: #P230
----------P035F------------------------------
PORT 035F - ARTEC Handyscanner A400Z. alternate address at 15F.
----------P03600367--------------------------
PORT 0360-0367 - PC network (XT only)
----------P0360036F--------------------------
PORT 0360-036F - PC network (AT)
----------P0360036F--------------------------
PORT 0360-036F - National Semiconductor DP8390(1)C/NS3249C network chipset
Note: cards based on this IEEE 802.3 networking chipset can use any range
of 16 consecutive addresses, and provide a total of four pages of
sixteen registers (see #P232,#P233,#P234,#P299)
(Table P232)
Values for NS DP8390C/NS3249C network chipset Page 0 registers:
Number Read Register Write Register
00h Command reg. (see #P236) CR Command reg. CR
01h current local DMA address 0 CLDA0 page start reg. PSTART
02h current local DMA address 1 CLDA1 page stop reg. PSTOP
03h boundary pointer BNRY boundary pointer BNRY
04h transmit status reg. TSR Tx page start address TPSR
05h number of collisions reg. NCR Tx byte count reg.0 TBCR0
06h FIFO Tx byte count reg.1 TBCR1
07h interrupt status reg. ISR interrupt status reg. ISR
08h current remote DMA address 0 CRDA0 remote start addr.reg.0 RSAR0
09h current remote DMA address 1 CRDA1 remote start addr.reg.1 RSAR1
0Ah reserved remote byte count reg.0 RBCR0
0Bh reserved remote byte count reg.1 RBCR1
0Ch receive status reg. RSR Rx configuration reg. RCR
0Dh tally counter 0 (frame errors) CNTR0 Tx configuration reg. TCR
0Eh tally counter 1 (CRC errors) CNTR1 data configuration reg. DCR
0Fh tally counter 2 (missed pkt) CNTR2 interrupt mask reg. IMR
SeeAlso: #P233,#P234,#P235
(Table P233)
Values for NS DP8390C/NS3249C network chipset Page 1 registers:
Number Read/Write
00h Command CR (see #P236)
01h physical address reg.0 PAR0
02h physical address reg.1 PAR1
03h physical address reg.2 PAR2
04h physical address reg.3 PAR3
05h physical address reg.4 PAR4
06h physical address reg.5 PAR5
07h current page reg. CURR
08h multicast address reg.0 MAR0
09h multicast address reg.1 MAR1
0Ah multicast address reg.2 MAR2
0Bh multicast address reg.3 MAR3
0Ch multicast address reg.4 MAR4
0Dh multicast address reg.5 MAR5
0Eh multicast address reg.6 MAR6
0Fh multicast address reg.7 MAR7
SeeAlso: #P232,#P234,#P235
(Table P234)
Values for NS DP8390C/NS3249C network chipset Page 2 registers:
Number Read Register Write Register
00h Command CR Command CR
01h page start reg. PSTART current local DMA addr.0 CLDA0
02h page stop reg. BPSTOP current local DMA addr.1 CLDA1
03h remote next packet pointer remote next packet pointer
04h Tx page start address TPSR reserved
05h local next packet pointer local next packet pointer
06h address counter (upper) address counter (upper)
07h address counter (lower) address counter (lower)
08h reserved reserved
09h reserved reserved
0Ah reserved reserved
0Bh reserved reserved
0Ch Rx configuration reg. RCR reserved
0Dh Tx configuration reg. TCR reserved
0Eh data configuration reg. DCR reserved
0Fh interrupt mask reg. IMR reserved
Note: this is a diagnostics page, and should never be modfied under normal
operation.
SeeAlso: #P232,#P233,#P235
(Table P235)
Values for NS DP8390C/NS3249C network chipset Page 3 registers:
Number Read Register Write Register
00h Command CR (see #P236) Command CR
Note: Test Page - should never be modified!
SeeAlso: #P232,#P233,#P234
Bitfields for NS DP8390C/NS3249C network chipset command register (00h):
Bit(s) Description (Table P236)
0 software reset command (1=offline, 0=online)
1 do not activate NIC after reset command
2 start transmision of a packet
3-5 remote DMA command
000 not allowed
001 remote read
010 remote write
011 send packet
1xx abort/complete rmote DMA
6-7 page select
00 register page 0
01 register page 1
10 register page 2
11 register page 3
SeeAlso: #P235
----------P036B------------------------------
PORT 036B - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 026Bh, PORT 02ABh (default), PORT 02EBh, PORT 032Bh,
PORT 03ABh, PORT 03EBh
----------P036C------------------------------
PORT 036C - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P03700377--------------------------
PORT 0370-0377 - FDC 2 (2nd Floppy Disk Controller) first FDC at 03F0
Note: floppy disk controller is usually an 8272, 8272A, NEC765 (or
compatible), or an 82072 or 82077AA for perpendicular recording at
2.88M
SeeAlso: PORT 03F0h-03F7h
0370 R- diskette Extra High Density controller board jumpers (AT)
0370 R- diskette controller status A (PS/2, PS/2 model 30)
0371 R- diskette controller status B (PS/2, PS/2 model 30)
0372 -W diskette controller DOR (Digital Output Register)
0374 R- diskette controller main status register
0374 -W diskette controller datarate select register
0375 RW diskette controller command/data register
0376 RW (2nd FIXED disk controller status/data register)
0377 RW (2nd FIXED disk controller drive address register)
0377 R- diskette controller DIR (Digital Input Register)
0377 -W select register for diskette data transfer rate
----------P0378------------------------------
PORT 0378 - Covox 'Speech Thing' COMPATIBLE SPEECH OUTPUT
SeeAlso: PORT 022Fh"mc-soundmachine",PORT 0388h-038Fh"soundmachine"
0378 -W speech output via printer port
(with mc-soundmachine, enabled if bit4=1 in 38F)
----------P0378037A--------------------------
PORT 0378-037A - PARALLEL PRINTER PORT (usually LPT2, sometimes LPT3)
Range: usually PORT 03BCh, PORT 0278h, or PORT 0378h
SeeAlso: MEM 0040h:000Ah,INT 17/AH=00h
0378 -W data port
0379 RW status port
037A RW control port
037B ?? bit 7: shadow RAM on/off (UniRAM adapter,according to c't 7/90)
----------P0380038F--------------------------
PORT 0380-038F - 2nd BSC (Binary Synchronous Communication) adapter
SeeAlso: PORT 03A0h"BSC"
----------P0380038C--------------------------
PORT 0380-038C - 2nd SDLC (Synchronous Data Link Control) adapter
Notes: Initialization of the SDLC adapter is performed in a typical
sequence like this: Setup 8255 port A-C configuration by writing
98h to 383h, followed by initializing 8255 port C by writing 0Dh
to 382h. Reset 8273 internal registers by pulsing 8255 port B4.
After this the 8253 has to be programmed to the desired values
(counter 0 in mode 3). Now the 8273 is ready to be configured for
the operating mode that defines the communication environment in
which it will be used.
Note on 8273: Each 8273 protocol controllers internal register is
programmed by individual set/reset commands (via 388h) in
conjunction with a parameter (via 389h) that give an OR/AND mask
to the internal register value.
Although the 8273 is a full duplex device, there is only one
command register. Thus, the command register must be used for
only one command sequence at a time and the transmitter and
receiver may never be simultaneously in a command phase.
The system software starts the command phase by writing a command
byte into the command register. If further information is required
by the 8273 prior to execution of the command, the system software
must write the list of parameters into the parameter register.
SeeAlso: PORT 03A0h"SDLC"
0380 R- on adapter 8255(A5) port A: internal/external sensing (see #P237)
0381 -W on adapter 8255(A5) port B: external modem interface (see #P238)
0382 RW on adapter 8255(A5) port C: internal control (see #P239)
0383 ?W on adapter 8255(A5) mode initialization
0384 RW on adapter 8253 (programmable counter) counter 0:
LSB / MSB square wave generator (input for timer 2, connected
to 8255 bitC5)
0385 RW on adapter 8253 counter 1: LSB / MSB inactivity time-outs
(connected to 8255 bitA7, IRQ4 level)
0386 RW on adapter 8253 counter 2: LSB / MSB inactivity time-outs
(connected to 8255 bitA6, IRQ4 level)
0387 ?W on adapter 8253 mode register (see #P240)
0388 R- on adapter 8273 status register (see #P241)
0388 -W on adapter 8273 command register (see #P242)
0389 R- on adapter 8273 (immediate) result register (see #P249)
0389 -W on adapter 8273 parameter register
Commands issued via PORT 0388h may need additional parameters,
which have to be passed through this port (see table).
038A R- on adapter 8273 transmit INT status (DMA/INT)
038A -W on adapter 8274 reset
038B R- on adapter 8273 receive INT status (DMA/INT)
038C -W on adapter 8273 data: direct program control (DPC)
scratch-pad
Bitfields for SDLC 8255 port A:
Bit(s) Description (Table P237)
7 =1 timer 1 output active
6 =1 timer 2 output active
5 =1 modem status changed
4 receive clock active (if pulsing)
3 =0 clear to send is on from interface
2 transmit clock active (if pulsing)
1 =0 data carrier detect is on from interface
0 =0 ring indicator is on from interface
SeeAlso: #P238,#P239
Bitfields for SDLC 8255 port B:
Bit(s) Description (Table P238)
7 enable IRQ 4 level interrupt
6 =1 gate timer 1
5 =1 gate timer 2
4 =1 reset 8273
3 =1 reset modem status changed logic
2 =0 turn on test
1 =0 turn on select standby at modem interface
0 =0 turn on data signal rate select at modem interface
SeeAlso: #P237,#P239
Bitfields for SDLC 8255 port C:
Bit(s) Description (Table P239)
7 R- =? not used (detection: =1 SDLC, =0 may be SDLC or BSC??)
6 R- =0 test indicate active
5 R- timer 0 output (if pulsing)
4 R- receive data (if pulsing)
3 -W =0 gate interrupts 3 and 4
2 -W =1 electronic wrap
1 -W =1 gate external clock
0 -W =1 gate internal clock
SeeAlso: #P237,#P238
Bitfields for SDLC 8253 mode register:
Bit(s) Description (Table P240)
7-6 SC1-SC0 00, 01, 10= select counter 0,1,2; 11=illegal
5-4 RL1-RL0 00= couner latching operation
01= read/load most significant byte (MSB)
10= read/load least significant byte (LSB)
11= read/load LSB first, then MSB
3-1 M2-M0 000= mode 0
001= mode 1
x10= mode 2
x11= mode 3
100= mode 4
101= mode 5
0 BCD 0= binary counter 16bits
1= BCD counter 4 decades
Bitfields for SDLC 8273 status register:
Bit(s) Description (Table P241)
7 =1 command busy (CBSY)
6 =1 command buffer full (CBF)
5 =1 command parameter buffer full (CPBF)
4 =1 command result buffer full (CRBF)
3 =1 Rx interupt (RxINT)
2 =1 Tx interupt (TxINT)
1 =1 RxINT result available (RxIRA)
0 =1 TxINT result available (TxIRA)
SeeAlso: #P242
(Table P242)
Values for SDCL 8273 command register:
commands: parameters: results: result port: int:
A4: set one-bit delay set mask - - no
64: reset one-bit delay reset mask - - no
97: set data transfer set mask - - no
57: reset data transfer reset mask - - no
91: set operating mode set mask - - no
51: reset operating mode reset mask - - no
A0: set serial I/O mode set mask - - no
60: reset serial I/O mode reset mask - - no
C0: general receive B0,B1 RIC,R0,R1,A,C RXI/R yes
C1: selective receive B0,B1,A1,A2 RIC,RD,R1,A,C RXI/R yes
C5: receive disable - - - no
C8: transmit frame L0, L1, A, C TIC TXI/R yes
C9: transmit transparent L0, L1 TIC TXI/R yes
CC: abort transmit frame - TIC TXI/R yes
CD: abort transmit - TIC TXI/R yes
22: read 8273 port A - port value result no
23: read 8273 port B - port value result no
A3: set 8273 port A bit set mask - - no
63: set 8273 port B bit reset mask - - no
Notes: B0/B1 LSB/MSB of the receiver buffer length
L0/L1 LSB/MSB of the Tx buffer length
A1/A2 receive frame address match field one/two
A address fieldof received frame. In non-buffered mode, this
result is not provided.
C control field of received frame. In non-buffered mode, this
result is not provided.
RXI/R TXI/R receive/transmit interrupt result register
R0/R1 LBS/MSB of the length of the frame received
RIC/TIC receiver/transmitter interrupt result code
SeeAlso: #P243,#P244,#P245,#P246,#P247,#P248
Bitfields for SDLC 8273 interal port A: Modem Control Input Port:
Bit(s) Description (Table P243)
7-5 not used
4 DSR change (PA4)
3 CTS change (PA3)
2 Data Set Ready (PA2)
1 Carrier Detect (PA1)
0 Clear to Send (PA0)
SeeAlso: #P242
Bitfields for SDLC 8273 interal port B: Modem Control Output Port:
Bit(s) Description (Table P244)
7-6 not used
5 Flag Detect (PB5)
4-3 reserved
2 Data Terminal Ready (PB2)
1 reserved (PB1)
0 Request to Send (PB0)
SeeAlso: #P242
Bitfields for SDLC 8273 internal: Operating Mode Register:
Bit(s) Description (Table P245)
7-6 not used
5 =1 HDLC abort enable
4 =1 EOP interrupt enable
3 =1 enable early Tx interrupt
2 =1 Buffered Mode
1 =1 Two Preframe Sync Characters
0 =1 Flag Stream Mode
SeeAlso: #P242
Bitfields for SDLC 8273 internal: Serial I/O Register:
Bit(s) Description (Table P246)
7-3 not used
2 =1 Data Loopback
1 =1 Clock Loopback
0 =1 NRZI Mode
SeeAlso: #P242
Bitfields for SDLC 8273 internal: Data Transfer Mode Register:
Bit(s) Description (Table P247)
7-1 not used
0 =1 Interrupt Data Transfers
SeeAlso: #P242
Bitfields for SDLC 8273 internal: One-Bit Delay Mode Register:
Bit(s) Description (Table P248)
7 =1 One-Bit Delay Enable
6-0 not used
SeeAlso: #P242
(Table P249)
Values for SDLC 8273 result register:
transmit result codes: status after interrupt:
0C: early transmit interrupt transmitter active
0D: frame transmit complete idle or flags
0E: DMA underrun abort
0F: clear to send error abort
10: abort complete idle or flags
receive result codes:
X0: A1 match / general receive active
X1: A2 match active
03: CRC error active
04: abort detected active
05: idle detected disabled
06: EOP detected disabled
07: frame less than 32 bits active
08: DMA overrun disabled
09: memory buffer overflow disabled
0A: carrier detect failure disabled
0B: receiver interrupt overrun disabled
X bits received inlast byte:
E: all eight bits of last byte (bit7-0)
0: bit0 only
8: bit1-0
4: bit2-0
C: bit3-0
2: bit4-0
A: bit5-0
6: bit6-0
--------s-P03840387--------------------------
PORT 0384-0387 - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
----------P03880389--------------------------
PORT 0388-0389 - AdLib - MONO SOUND OUTPUT
Note: also supported by SoundBlaster and compatibles
SeeAlso: PORT 0220h-0223h,PORT 0388h-038Fh"soundmachine"
0388 R- both speakers -- Status
bit7 : interrupt request (IRQ)
bit6 : timer 1 overflow
bit5 : timer 2 overflow
bit4-0: reserved
0388 -W both speakers -- Address port (see #P250)
index in OPL2 (YMF3812), OPL3 (YMF262), OPL4 (YF278-F)
0389 -W data port
Note: the AdLib requires a delay of 3.3 microseconds between writing to
PORT 0388h and writing to PORT 0389h, and a delay of 23 microseconds
after a write to PORT 0389h before any other operation is allowed
(Table P250)
Values for AdLib address port index:
01h Enable waveform control
bit 7-6: (OPL4, OPL3 in OPL2 mode only) lsi test
bit 5: (OPL2 only) wave select enable (WS)
(OPL4, OPL3) lsi test
bit 4-0: lsi test
02h Timer #1 data (OPL2 and OPL3 in OPL2 mode only)
03h Timer #2 data (OPL2 and OPL3 in OPL2 mode only)
04h Timer control flags (OPL2 and OPL3 in OPL2 mode only)
bit 7 : reset interrupt (RST)
bit 6 : timer 1 mask (MASK1)
bit 5 : timer 2 mask (MASK2)
bit 4-2: reserved
bit 1 : start timer 2 (ST2)
bit 0 : start timer 1 (ST1)
04h (OPL3 in OPL3 mode only) connection select
bit 7-6: reserved
bit 5-0: connection selection
05h (OPL3) compatibility register
bit 7-1: reserved
bit 0: enable OPL3 mode (NEW), default disabled
08h Speech synthesis mode
bit 7: (OPL2 only) speech synthesis or FM music mode (CSM)
bit 6: select keyboard split point (SEL/NTS)
bit 5-0: reserved
20h-35h Amplitude Modulation / Vibrato
bit 7: AM modulation (AM)
bit 6: vibrato (VIB)
bit 5: sustain (EG)
bit 4: keyboard scaling rate (KSR)
bit 3-0: multi (MF)
40h-55h Level key scaling / Total level
bit 7-6: key scale level (KSL)
bit 5-0: total level (TL)
60h-75h Attack / Decay rate
bit 7-4: attack rate
bit 3-0: decay rate
80h-95h Sustain / Release rate
bit 7-4: sustain level
bit 3-0: release rate
A0h-A8h Octave / Frequency (LSB)
A9h-AFh ???
B0h-B8h Octave / Frequency Number
bit 7-6: reserved
bit 5 : key on, mute
bit 4-2: block, octave
bit 1-0: f-number (MSB)
BDh percussion, vibrato, AM (OPL2, OPL3 in OPL2 mode only)
bit 7: amplitude modulation (AM)
bit 6: vibrato (VIB)
bit 5: ryhthm, percussion on/off (R)
bit 4: bass drum on/off (BD)
bit 3: snare drum on/off (SD)
bit 2: tom-tom on/off (TOM)
bit 1: top cymbal on/off (TC)
bit 0: hi hat on/off (HH)
C0h-C8h Feedback / Algorithm
bit 7-4: OPL3: channel D-A
bit 3-1: feedback
bit 0: connection
E0h-F5h Waveform Selection
bit 7-3: reserved
bit 2 : (OPL3) waveform bit2
bit 1-0: waveform
SeeAlso: #P251
(Table P251)
Values for Sound Blaster registers inside groups:
Offset
+00..+02: operators 1-3 modulator channel 1-3
+03..+05: operators 4-6 carrier channel 1-3
+08..+0A: operators 7-9 modulator channel 4-6
+0B..+0D: operators 10-12 carrier channel 4-6
+10..+12: operators 13-15 modulator channel 7-9
+13..+15: operators 16-18 carrier channel 7-9
+06, +07, +0E, +0F: reserved
SeeAlso: #P250
----------P03880389--------------------------
PORT 0388-0389 - Soundblaster PRO FM-Chip
----------P0388038B--------------------------
PORT 0388-038B - Soundblaster 16 ASP FM-Chip
--------s-P0388038B--------------------------
PORT 0388-038B - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
----------P0388038F--------------------------
PORT 0388-038F - mc-soundmachine, mc 03-04/1992 - SPEECH I/O
Note: Adlib-compatible, Covox 'voice master' & 'speech thing' compatible
soundcard
SeeAlso: PORT 022Fh"soundmachine",PORT 0278h"Covox"
0388 -W Covox 'speech thing' compatible speech output via printer port?
enabled if bit 6 set in PORT 038Fh
0388 RW Adlib compatible (YM3812), enabled if bit 0 set in PORT 038Fh
(see PORT 0388h-0389h"Sound Blaster")
0389 -W Adlib compatible (YM3812), enabled if bit 0 set in PORT 038Fh
(see PORT 0388h-0389h"Sound Blaster")
038A -W I²C control for TDA7302 NF-MUX and X24C04 EEPROM
bit 7: I²C bus SDA out (data), enabled if bit2=1 in PORT 038Fh
bit 0: I²C bus SCL out (clock), enabled if bit2=1 in PORT 038Fh
038B R- I²C status for TDA7302 NF-MUX and X24C04 EEPROM
bit 7: I²C bus SDA in (data), enabled if bit2=1 in PORT 038Fh
bit 0: I²C bus SCL in (clock), enabled if bit2=1 in PORT 038Fh
038F RW configuration port (power on default=0, all features disabled)
(see #P252)
Bitfields for mc-soundmachine configuration port:
Bit(s) Description (Table P252)
7 Covox 'voice master' enabled at PORT 022Fh
6 "" 'speech thing' enabled at PORT 03BCh
5 "" enabled at PORT 0278h
4 "" enabled at PORT 0378h
3 not used (0388???)
2 I²C bus enabled (see PORT 038Ah,PORT 038Bh)
1 gameport enabled (see PORT 0201h)
0 AdLib registers (see PORT 0388h,PORT 0389h) enabled
--------s-P038C038F--------------------------
PORT 038C-038F - Pro Audio Spectrum 16 (PAS16)
Range: PORT 0280h, PORT 0284h, PORT 0288h, PORT 028Ch, PORT 384h,
PORT 0388h (default), or PORT 038Ch
----------P03900397--------------------------
PORT 0390-0397 - Sunshine EW-901B, EW-904B
EPROM writer card for EPROMs up to 27512
0390-0393 ?? adresses of the 8255 on the EW-90xB
----------P0390039F--------------------------
PORT 0390-039F - Cluster adapter (AT)
0390 ?? (adapter 0) (XT)
0391 ?? (adapter 0) (XT)
0392 ?? (adapter 0) (XT)
0393 ?? (adapter 0) (XT)
----------P03980399--------------------------
PORT 0398-0399 - Dell Enhanced Parallel Port
SeeAlso: PORT 002Eh,PORT 015Ch,PORT 026Eh
0398 -W index for data port
0399 RW EPP command data
----------P03A003AC--------------------------
PORT 03A0-03AC - 1st SDLC (Binary Synchronous Data Link Control adapter)
SeeAlso: PORT 0380h"SDLC"
----------P03A003AF--------------------------
PORT 03A0-03AF - 1st BSC (Binary Synchronous Communication) adapter
Notes: Initialization of the BSC adapter is performed in a typical
sequence like this: Setup 8255 port A-C configuration by writing
98h to 383h, followed by initializing 8255 port C by writing 0Dh
to 382h. Reset 8251A internal registers by pulsing 8255 port B4.
After this the 8253 has to be programmed to the desired values
(counter 0 not used, counters 1 and 2 to mode 0). Now, the 8251A
is ready to be loaded with a set of control words that define the
communication environment.
8251A: The control words are split into two formats, mode
instruction and command instruction. The mode instruction must
be inserted immediately after a reset operation (via 8255 port B4
or setting command instruction bit6 to 'internal reset').
The required synchronization characters are next loaded into the
8251A (usually 32h for BSC). All control words written to the
8251A after this will load the command instruction.
reset -> mode instruction
SYNC character 1
SYNC character 2
command instruction
data ...
command instruction
data ...
command instruction
...
SeeAlso: PORT 0380h"BSC"
03A0 R- on adapter 8255(A5) port A: internal/external sensing (see #P253)
03A1 -W on adapter 8255(A5) port B: external modem interface (see #P254)
03A2 RW on adapter 8255(A5) port C: internal control (see #P255)
03A3 ?W on adapter 8255(A5) mode initialization
03A4 RW on adapter 8253 (programmable counter) counter 0:
LSB / MSB square wave generator (unused in sync mode)
03A5 RW on adapter 8253 counter 1: LSB / MSB inactivity time-outs
(connected to 8255 bitA7, IRQ4 level)
03A6 RW on adapter 8253 counter 2: LSB / MSB inactivity time-outs
(connected to 8255 bitA6, IRQ4 level)
03A7 ?W on adapter 8253 mode register (see #P256)
03A8 RW on adapter 8251: data (see #P257)
03A9 R- on adapter 8251: command/mode/USART status register (see #P258)
Bitfields for BSC 8255 port A:
Bit(s) Description (Table P253)
7 =1 timer 1 output active
6 =1 timer 2 output active
5 =1 TxRDY active
4 receive clock active (if pulsing)
3 =0 clear to send is on from interface
2 transmit clock active (if pulsing)
1 =0 data carrier detect is on from interface
0 =0 ring indicator is on from interface
SeeAlso: #P254
Bitfields for BSC 8255 port B:
Bit(s) Description (Table P254)
7 =1 enable IRQ 4 level interrupt (timer 1 and 2)
6 =1 gate timer 1
5 =1 gate timer 2
4 =1 reset 8251A
3 =1 not used
2 =0 turn on test
1 =0 turn on select standby
0 =0 turn on data signal rate select
SeeAlso: #P253,#P255
Bitfields for BSC 8255 port C:
Bit(s) Description (Table P255)
7 R- =0 BSC adapter (=1 may be used to detect SDLC??)
6 R- =0 test indicate active
5 R- timer 0 output (if pulsing)
4 R- receive data (if pulsing)
3 -W =0 enable timer 1 and 2 IRQ4 and receive IRQ 4
2 -W =1 electronic wrap
1 -W =1 gate external clock
0 -W =1 gate internal clock
SeeAlso: #P253,#P254
Bitfields for BSC 8253 mode register:
Bit(s) Description (Table P256)
7-6 SC1-SC0 00, 01, 10= select counter 0,1,2; 11=illegal
5-4 RL1-RL0 00= couner latching operation
01= read/load most significant byte (MSB)
10= read/load least significant byte (LSB)
11= read/load LSB first, then MSB
3-1 M2-M0 000= mode 0 (for counter 1 and 2)
001= mode 1 (not used for BSC)
x10= mode 2 (not used for BSC)
x11= mode 3 (not used for BSC)
100= mode 4 (not used for BSC)
101= mode 5 (not used for BSC)
0 BCD 0= binary counter 16bits
1= BCD counter 4 decades
Bitfields for BSC 8251 data:
Bit(s) Description (Table P257)
---mode instruction (W)---
7 =0 Double SYNC Character
6 =1 SYNDET is an Input
5 =1 Even Parity
4 =1 Parity Enable
3-2 Character Length 00=5bits, 01=6bits, 10=7bits, 11=8bits
1-0 not used (always 0)
---SYNC character 1/2 (W)---
string of two characters to be sync'ed at (in hunt mode).
---command instruction (W)---
7 Enter Hunt Mode
6 Internal Reset
5 Request to Send
4 Error Reset
3 Send Break Character
2 Receive Enable
1 Data Terminal Ready
0 Transmit Enable
---data (RW)---
any data
SeeAlso: #P256,#P258
Bitfields for BSC 8251 command/mode/USART status:
Bit(s) Description (Table P258)
7 Data Set Ready (indicated that DSR is at 0 level)
6 SYNDET
5 Framing Error (not used for synchronous communications)
4 Overrun Error (OE flag on when Overrun Error occurs)
3 Parity Error (PE flag on when a parity error occurs)
2 TxEmpty
1 RxRDY (causing IRQ 3 level)
0 TxRDY (has not the same meaning as 8251A TxRDY output pin).
THIS one is NOT conditioned by CTS and TxEnable (causing IRQ 4 level)
SeeAlso: #P257
----------P03AB------------------------------
PORT 03AB - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 026Bh, PORT 02ABh (default), PORT 02EBh, PORT 032Bh,
PORT 036Bh, PORT 03ABh, PORT 03EBh
----------P03AC------------------------------
PORT 03AC - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P03B003BF--------------------------
PORT 03B0-03BF - MDA (Monochrome Display Adapter based on 6845)
03B0 -W same as 03B4
03B1 RW same as 03B5
03B2 -W same as 03B4
03B3 RW same as 03B5
03B4 -W MDA CRT index register (MDA/mono EGA/mono VGA)
selects which register (0-11h) is to be accessed through 03B5h
Note: this port is read/write on some VGAs
bit7-6: (VGA) reserved (0)
bit5 : (VGA) reserved for testing (0)
bit4-0: selects which register is to be accessed through 03B5h
03B5 RW MDA CRT data register (MDA/mono EGA/mono VGA) (see #P259)
selected by PORT 03B4h. registers 0C-0F may be read
Color adapters are at 3D4/3D5, but are mentioned here for
better overview.
There are differences in names and some bits functionality
on EGA, VGA in their native modes, but clones in their
emulation modes emulate the original 6845 at bit level. The
default values are for MDA, HGC, CGA only, if not otherwise
mentioned.
03B6 -W same as 03B4h
03B7 RW same as 03B5h
03B8 rW MDA mode control register (see #P260)
03B9 ?W reserved for color select register on color adapter
03B9 -W MDA/HGC: set lightpen flipflop (value written is ignored)
cannot be found on native mono EGA, mono VGA (without
translation ROM)
03BA R- CRT status register (see #P261)
(EGA/VGA) input status 1 register
03BA -W (mono EGA/mono VGA) feature control register
(see PORT 03DAh-W for details; VGA, see PORT 03CAh-R)
03BB -W light pen strobe reset (on any value)
(Table P259)
Values for mono video adapter CRT data register index:
defaults: MDA/HGC HGC CGA CGA CGA
text graph text1 text2 graph
7 720x348 1 3 5,6
00h horizontal total 61h 35h 38h 71h 38h
ET4000: in VGA mode scanlines-5
in EGA mode scanlines-2
01h horizontal displayed 50h 2Dh 28h 50h 28h
horizontal display end-1 (EGA,VGA)
02h horizontal sync position 52h 2Eh 2Dh 5Ah/5Ch 2Dh
03h sync pulse width 0Fh 07h/0Fh 0Ah 0Ah 0Ah
bit7-4 vsync, bit3-0 hsync
end horizontal blanking (EGA,VGA)
VGA : bit7=1 : enable read access to regs
10h, 11h (otherwise VGA clones
may show lightpen values)
EGA,VGA: bit6-5=0-3: display enable skew control
bit4-0 : end blanking
04h vertical total (vcycle-1) 19h 5Bh 1Fh 1Fh 7Fh
bit7 only used on MCGA
start horizontal retrace (EGA, VGA)
Genoa SuperEGA only???:
bit7 : start at odd memory address
bit6-5: horizontal sync skew
bit4-0: start retrace+ retrace width
05h vertical total adjust 06h 02h 06h 06h 06h
bit7-5 only used on MCGA
end horizontal retrace (EGA, VGA)
bit7 : (EGA) start at odd memory address
(VGA) bit5 of end horizontal retrace
bit6-5: horizontal sync skew
bit4-0: end horizontal retrace
06h vertical displayed 19h 57h 19h 19h 64h
bit7 only used on MCGA
(EGA) vertical total-1
(VGA) vertical total-2
07h vertical sync pulse width-1 19h 57h 1Ch 1Ch 70h/66h
bit7 only used on MCGA
controller overflow (EGA,VGA)
bit7: (VGA) bit9 of start vertical retrace (10h)
bit6: (VGA) bit9 of vertical display end (12h)
bit5: (VGA) bit9 of vertical total (06h)
(EGA) bit5 of cursor-position (0Ah)
bit4: bit8 of line compare (18h)
bit3: bit8 of start vertical blanking (15h)
bit2: bit8 of vertical retrace start (10h)
bit1: bit8 of vertical display end (12h)
bit0: bit8 of vertical total (06h)
08h interlace mode (not MCGA) 02h 02h 02h 02h 02h
bit7-2: reserved
bit1 : delay
bit0=1: interlace on
preset row scan (EGA, VGA)
bit7 : reserved
bit6-5: (VGA) byte panning
bit4-0: start row scan after retrace
09h maximum scan lines 0Dh 03h 07h 07h 01h
bit7 : (VGA) double scan active
bit6 : (VGA) bit9 of line compare (18h)
bit5 : (VGA) bit9 of start vertical blanking (15h)
bit4-0: maximum scan line 00..31 (height-1)
0Ah cursor start 0Bh 00h 06h 06h 06h/00h
bit7 : reserved
bit6-5: original 6845: cursor on/off, blink interval
(not on all adapters, as original MDA, CGA have
extra circuitrity to avoid this!!)
bit6-5: native EGA: not used
bit6 : (VGA) not used
bit5=0: (VGA) cursor on
bit4-0: first cursor scanline
0Bh cursor end 0Ch 00h 07h 07h 07h/00h
bit7 : reserved
bit6-5: EGA, VGA: cursor skew control
bit4-0: end cursor row
0Ch RW start address high 00h 00h 00h 00h 00h
bit7-6 not used by original 6845 (MDA,HGC,CGA)
0Dh RW start address low 00h 00h 00h 00h 00h
0Eh RW cursor location high 00h 00h 00h 00h 00h
bit7-4 not used by original 6845 (MDA,HGC,CGA)
bit5-4 reserved on MCGA
0Fh RW cursor location low 00h 00h 00h 00h 00h
10h R- light pen high (MDA/CGA/EGA only, some HGC, few VGA
clones in emulation, not with ET4000)
10h R- MCGA at 3D5h only: mode control status register (see #P288)
11h R- light pen low (MDA/CGA/EGA only, some HGC, few VGA
clones in emulation, not with ET4000)
14h -W HGC+,InColor: xMode register
15h -W HGC+,InColor: underscore register
16h -W HGC+,InColor: overstrike register
17h -W InColor: exception register
18h -W InColor: plane mask register
19h -W InColor: read/write control register
1Ah -W InColor: read/write color register
1Bh -W InColor: Latch Protect register
1Ch RW InColor: palette register
Notes: registers 10h and 11h have varying uses on VGA (see #P286) and
MCGA (see #P287)
MDA, HGC, CGA: 6845 registers 00h-0Dh are write only, 0Eh, 0Fh
are r/w, and 10h-11h are read only.
The alternative initial defaults may be used
sometimes on modern adapters.
HGC+(RamFont): as with HGC, but 3 additional registers for font control
emulations : more registers may be r/w, but most often it's the
same as with native 6845.
MCGA (CGA+) : Though this is a mixture of CGA and VGA, most
registers are same as with CGA, but with some
enhancements and incompatibilities to EGA, VGA.
native EGA : registers 00h-0Bh are write only, 0Ch-0Fh are
r/w, 10h-11h are read/write, 12h-18h are write
only. More regs may be r/w on enhanced clones.
GenoaSuperEGA: adapter with chips SEQCRT GN006001 and GRAT
GN006002, e.g. c't Super-EGA adapter. Is EGA
clone with up to 800x600 and full 6845 emulation.
native VGA : all registers 00-18h are r/w, but 00h-07h are
write-locked if bit7 in 11h is set.
ET4000 : same as VGA, but with additional r/w registers
32h-37h, protected by 'key' except 33h, 35h
(see 3BFh for details). 35h is protected by
bit7 in 11h. The 'key' must be issued at least
after each power on or synchronous reset.
SeeAlso: #P286,#P287,#P260,#P261,#P287
Bitfields for mono video adapter mode control register:
Bit(s) Description (Table P260)
7 not used by MDA, page number on HGC
6 not used
6 R-O (mono ET4000 only) report status of bit 1 (enable 2nd page) of
Hercules compatibility register (PORT 03BFh)
5 enable blink (0 = intense background, 1 = blink)
4 not used
3 video enable
2 not used
1 (MDA) not used
(HGC) graphics enable
the 6845 has to be reprogrammed completely, if this bit is
changed, otherwise the TTL-monitor may be damaged by wrong
sync impulses!
0 high resolution mode (always set on MDA)
---mono ET4000 only, W-O ---
7-0 =A0h: second part of 'key', see Hercules compatibility register
(PORT 03BFh) for details
Note: this port might be completely or partially readable on very few MDA,
HGC clones or emulations (e.g. Genoa SuperEGA), but not with the
majority of original and clone chips. It cannot be found on
native mono EGA, mono VGA, but on most clones, where it is usually
R/W.
SeeAlso: #P259,#P261
Bitfields for mono video adapter CRT status register:
Bit(s) Description (Table P261)
7 HGC: vertical sync pulse in progress
6-4 adapter identification
(MSD says) if bit 7 changes within 8000h reads then
=000 adapter is Hercules or compatible
=001 adapter is Hercules+
=101 adapter is Hercules InColor
else: adapter is unknown
6-4 =111 on MDA and some HGC clones
5-4 (mono EGA, mono ET4000) diagnose video display feedback
select from color plane enable
3 (MDA,HGC) pixel stream (0=currently black, 1=currently white)
(mono EGA, mono VGA) vertical retrace in progress
2-1 (MDA) reserved
2 (HGC, mono EGA) lightpen flipflop set
(mono ET4000) reserved (0)
1 (HGC) lightpen input stream (if set, current value to get from
PORT 03B5h registers 10h-11h)
(mono ET4000) reserved (0)
0 horizontal drive enabled
SeeAlso: #P259,#P260
Bitfields for EGA,VGA mode control register:
Bit(s) Description (Table P262)
7 0=CRTC reset and stop, 1=resume reset
6 0=word-mode, 1=byte-mode (VGA: see 14h, bit6)
5 0=14bit, 1=16bit address wrap
4 (native VGA only) reserved (0)
4 (EGA and most VGA clones) output control
0: video driver active
1: video driver not active
3 linear address counter clock (0 = standard, 1 = clock/2)
(VGA: see register 14h, bit 5)
2 horizontal retrace clock (0 = standard, 1 = clock/2)
1 row scan counter
0: address bit 14 = scan bit 1
1: address bit 14 not altered
0 6845 compatibility mode
0: address bit 13 = scan bit 0 (as with 6845)
1: address bit 13 not altered
SeeAlso: #P259
----------P03BC03BF--------------------------
PORT 03BC-03BF - PARALLEL PRINTER PORT (MDA's LPT1)
Range: PORT 0278h, PORT 0378h, or PORT 03BCh
SeeAlso: MEM 0040h:0008h
03BC -W data port
03BC R- bidirectional port: input from connector
unidirectional port: last value written to port
03BD RW status port (see #P263)
03BE RW control port (see #P264)
Bitfields for parallel interface status port:
Bit(s) Description (Table P263)
7 busy
6 NOT acknowledge (approx. 5us low pulse)
5 out of paper
4 printer is selected
3 *no* error
2 IRQ has *not* occurred
(PS/2) printer returned -ACK
1-0 reserved
SeeAlso: #P264
Bitfields for parallel interface control port:
Bit(s) Description (Table P264)
7-5 reserved
7 (see PORT 037Bh bit 7)
5 enable bidirectional port
(PS/2 also requires enabling via PORT 0102h)
4 enable IRQ (via -ACK)
3 select printer (SLCT IN line)
2 =0 initialize printer (-RESET line)
1 automatic line feed
0 strobe (must be set for minimum of 5 microseconds)
SeeAlso: #P263
----------P03BF------------------------------
PORT 03BF - Hercules configuration switch register
Note: can also be found on EGA and VGA clones in Hercules emulation
03BF -W configuration switch register (see #P265)
03BF -W (ET4000) Hercules compatibility register (see #P266)
03BF RW (Genoa SuperEGA) miscellaneous register
Note: only available in MDA, HGC, and CGA emulation; should be
compatible with Hercules configuration register, but may contain
additional features
Bitfields for Hercules configuration switch register:
Bit(s) Description (Table P265)
7-2 reserved
1 =0 disables upper 32K of graphics mode buffer
=1 enables upper 32K of graphics mode buffer
0 =0 prevents graphics mode
=1 allows graphics mode
SeeAlso: #P266
Bitfields for ET4000 compatibility register:
Bit(s) Description (Table P266)
1 =0 disables upper 32K of graphics mode buffer
=1 enables upper 32K of graphics mode buffer
0 reserved (not needed for HGC graphics)
7-0 =03h: first part of 'key' for access to some extra
ET4000 regs. To issue the 'key', the following
code must be executed:
MOV DX, 3BFh
MOV AL, 3
OUT DX, AL
MOV DX, 3D8h (3B8h in mono mode)
MOV AL, 0A0h
OUT DX, AL
SeeAlso: #P265
----------P03C003C7--------------------------
PORT 03C0-03C7 - Sunshine EW-901, EW-901A, EW-904, EW-904A
EPROM writer card for EPROMs up to 27512
03C0-03C3 adresses of the 8255 on the EW-90x
----------P03C003CF--------------------------
PORT 03C0-03CF - EGA (1st Enhanced Graphics Adapter) alternate at 02C0
03C0 rW EGA VGA ATC index/data register
Every write access to this register will toggle an internal
index/data selection flipflop, so that consecutive writes to
index & data is possible through this port. To get a defined
start condition, each read access to the input status register
#1 (3BAh in mono / 3DAh in color) resets the flipflop to load
index. If values are changed during the vertical retrace
period only no flicker will occur.
index register (flipflop reset to 'index'): (default 20h)
bit7-6: reserved
bit5 : 0=CPU access (screen dark),
1=video access to registers
bit4-0: index in ATC (0..31)
indexed registers in ATC (flipflop set to 'data'): (see #P267)
03C1 R- VGA ATC index/data read register
03C2 R- EGA VGA input status 0 register
(Genoa SuperEGA in all emulation modes)
bit6-5 are 'key' protected on ET4000.
bit7 : CRT interrupt occured
EGA: 0=vertical retrace in progress, 1=display
bit6 : EGA and ET4000: feature control 1 (pin17)
bit5 : EGA and ET4000: feature control 0 (pin19)
bit4 : DIP switch sense
(0=closed, 1=open/switches readable)
bit3-0: reserved
03C2 -W EGA VGA miscellaneous output register (see #P278)
03C3 RW VGA video subsystem enable (see also PORT 46E8h)
for IBM, motherboard VGA only
bit7-4=0: reserved
bit3 : select video subsystem (address 46E8h)
bit2-1 : reserved
bit0 : select video subsystem (address 03C3)
03C4 -W EGA TS index register
03C4 RW VGA sequencer index register (see also #P273)
bit7-3 : reserved (VGA only)
bit2-0 : current TS index
03C5 -W EGA TS data register
03C5 RW VGA sequencer data register (see #P273)
03C6 RW (VGA, MCGA) PEL mask register (default FFh)
VGA: AND mask for color-register address.
MCGA: Never change from the default FFh.
03C6 RW HiColor ET4000 (Sierra RAMDACs e.g. SC11486, SC11481, SC11488):
Enable HiColor feature: beside other assignments,
consequtive read 3C6h 4 times and write magic value 80h to it.
03C7 -W (VGA,MCGA,CEG-VGA) PEL address register (read mode)
Sets DAC in read mode and assign start of color register
index (0..255) for following read accesses to 3C9h.
Don't write to 3C9h while in read mode. Next access to
03C8h will stop pending mode immediatly.
03C7 -W (CEG-Color VGA w/ Edsun Labs RAMDACs)
Enable and set Countinous Edge Graphics Mode:
Consecutive write the following three key sequences in read
mode (!) to 3C9h register DEh : 'CEG', 'EDS', 'UNx' (x see
below). Current CEG mode can be read from palette register
BFh 'blue', write access to that register will disable CEG
features.
In CEG modes by combining old with new colors and dynamically
changing palette values, the effective colors displayable
are enhanced dramatically (in EDP modes up to virtually 32bit
truecolor) on standard 16/256 color VGA. Also, effective
resolution enhancement takes effect by anti-aliasing.
Necessary EDP escape sequences should be moved to image
border or single colored areas, if possible.
REP-mode: if pixel are doubled in current video mode
EDP-mode: pseudo-truecolor with Edsun dynamic palette
(see #P283,#P284)
Palette-color-register single-byte-format (each 3 times):
Mode A: Mode C:
bit7-4: mix code bit3 : 0=color, 1=code
bit3-0: color code bit2-0: color / mix code
Mode B: Mode D:
bit7-5: mix code bit7-0: see mix code table
bit4 : 0=new, 1=old Non-CEG modes:
bit3-0: color code bit7-0: as usual
In EDP modes, video-memory-palette-changing escape-sequences:
Mode A: Mode B: Mode C: Mode D:
7/escape 7/escape 7/escape 0BFh
red red red7-4 red
green green red3-0 green
blue blue green7-4 blue
address address green3-0 address
blue7-4
blue3-0
address
03C7 R- VGA DAC state register
bit7-2 reserved
bit1-0: 00b write palette cycle (write mode)
01h reserved
10b reserved
11b read palette cycle (read mode)
03C8 RW (VGA,MCGA) PEL address register (write mode)
Sets DAC in write mode and assign start of color register
index (0..255) for following write accesses to 3C9h.
Don't read from 3C9h while in write mode. Next access to
03C8h will stop pending mode immediatly.
03C8 RW (Genoa SuperEGA) SuperEGA control register (all emulation modes)
bit7-2: reserved
bit1 : 0=EGA mode, 1=backward compatibility mode
bit0 : not used
03C9 RW (VGA,MCGA) PEL data register
Three consequtive reads (in read mode) or writes (in write
mode) in the order: red, green, blue. The internal DAC index
is incremented each 3rd access.
bit7-6: HiColor VGA DACs only: color-value bit7-6
bit5-0: color-value bit5-0
03CA -W EGA graphics 2 position register
03CA R- VGA feature control register (see PORT 03BAh,PORT 03DAh-W)
03CB RW (ET4000/W32) GDC segment select register 2 ('key' protected?)
The existence of this r/w register 0..255 is often
used to decide between ET4000 and ET4000/W32.
bit7-6: reserved, but existent
bit5-4: bits 5-4 of read segment pointer
bit3-2: reserved, but existent
bit1-0: bits 5-4 of write segment pointer
03CC -W EGA graphics 1 position register
03CC R- VGA miscellaneous output register (see PORT 03C2h-W,#P278)
03CD RW (ET3000, ET4000, ET4000/W32) GDC segment select ('key' protected)
The existence of this r/w register is often used as
detection of ET3000, ET4000 and ET4000/W32 chips.
bit7-4: read segment pointer for mapping to A0000h
bit3-0: write segment pointer for mapping to A0000h
03CE -W EGA GDC index register
03CE RW VGA graphics address register / GDC index
bit7-4: reserved
bit3-0: index
03CF -W EGA GDC data register
03CF RW VGA other graphics register (see #P279)
(Table P267)
Values for EGA/VGA indexed registers in ATC:
00h-0Fh 16 palette registers (see #P268)
10h mode control register (see #P269)
11h (EGA) overscan color register (see #P270) (default: 00h)
11h (VGA) overscan color register (see #P271) (default: 00h)
12h color enable register (see #P272)
13h horizontal pixel panning register
bit7-4: reserved
bit3-0: horizontal pixel panning
14h (VGA) color select register (default: 00h)
bit7-4: reserved
bit3 : s-color 7
bit2 : s-color 6
bit1 : s-color 5 (only with 16 pages á 16 regs)
bit0 : s-color 4 (only with 16 pages á 16 regs)
16h ET3000, ET4000 only: ATC miscellanenous
(at least on ET4000 'key' protected)
This register is also supported by ET3000, but the
description is proved for ET4000 only.
bit7 : bypass the internal palette
(e.g. for HiColor modes with Sierra RAMDACs)
bit6 : reserved
bit5-4: select high resolution / color mode
bit3-0: reserved
SeeAlso: #P273,#P279
Bitfields for EGA/VGA indexed ATC palette register:
Bit(s) Description (Table P268)
7-6 reserved
5 secondary red video
4 secondary green/intensity video
3 secondary blue/mono video
2 primary red video
1 primary green video
0 primary blue video
SeeAlso: #P267
Bitfields for EGA/VGA ATC mode control register:
Bit(s) Description (Table P269)
7 (VGA) SB/SG select (0=4 pages of 64 regs, 1=16 pages of 16 regs)
6 (VGA) PELCLK/2 (0=4bit color, 1=8bit color)
5 (VGA) enable pixel panning (0=all, 1=up to line compare register value)
4 reserved
3 background intensity (0=16 colors, 1=blink)
2 line graphics enable (0=background, 1=line 8=9)
1 1=mono, 0=color select
0 1=graphics, 0=text select
SeeAlso: #P267
Bitfields for EGA overscan color register:
Bit(s) Description (Table P270)
7-6 reserved
5 secondary red (SR)
4 secondary green (SR) / intensity
3 secondary blue (SB)
2 primary red (PR)
1 primary green (PG)
0 primary blue (PB)
SeeAlso: #P267,#P271
Bitfields for VGA overscan color register:
Bit(s) Description (Table P271)
7 secondary intensity border color (SI)
6 secondary red (SR)
5 secondary green (SG)
4 secondary blue (SB)
3 intensity border color (PI)
2 primary red (PR)
1 primary green (PG)
0 primary blue (PB)
SeeAlso: #P267,#P270
Bitfields for EGA/VGA color enable register:
Bit(s) Description (Table P272)
7-6 reserved
5-4 diagnose / video status select
EGA: VGA, ET4000:
00b = PR/PB PR/PB
01b = SB/PG SG/SB
10b = SR/SG PI/PG
11b = reserved SI/SR
3 enable plane 3
2 enable plane 2
1 enable plane 1
0 enable plane 0
SeeAlso: #P267
(Table P273)
Values for EGA/VGA indexed TS (sequencer) registers:
00h reset register
bit7-2 : reserved
bit1 =0: synchronous reset (EGA/VGA)
bit0 =0: asynchronous reset (EGA, ET4000)
synchronous reset, also (VGA)
01h clocking mode register / TS mode (see #P274)
02h map mask register (see #P275)
03h character map select register / font select (see #P276)
04h memory mode register
bit7-4 : reserved
bit3 =1: (VGA) enable chain 4 linear graphics mode
bit2 : 0=odd/even mode, 1=sequential mode
bit1 =1: extended memory (0=64KB, 1=more)
bit0 : (EGA) 1=textmode, 0=graphics mode
06h ET3000 only: Zoom control register
06h ET4000 only: TS state control (protected by 'key')
bit7-3 : reserved
bit2-1 : timing sequencer state bit2-1
(bit0 is bit0 TS mode register)
00 0b= 9 dots
00 1b= 8 dots
01 0b= 10 (10-16 are ET4000 only)
01 1b= 11
10 0b= 12
11 1b= 16
bit0 : reserved
07h ET3000/ET4000 only: TS auxiliary mode (see #P277)
08h S3 864/964/765 (Trio64V): key register -- enable access to S3 extended
registers when set to 06h
---S3 756 (Trio64V) extended registers---
09h "SR09" ???
bit 7: enable register access via either memory-mapped I/O or ports
0Bh ???
bits 7-4: ???
0Dh DPMS
bits 7-4: DPMS power mode
0000 On
0001 Standby
0100 Suspend
0101 Off
bits 1-0: ???
10h ??? \
11h ??? / paired
12h ??? \
13h ??? / paired
15h ???
bit 4: ???
18h bit 5 set while reduced-power modes active
bit 7: ???
1Ch bit 0: enable memory-mapped 8514/A registers at 000A0000h
bit 1: enable memory-mapped 8514/A registers at LFB+01000000h
Bitfields for EGA/VGA sequencer clocking mode register:
Bit(s) Description (Table P274)
7-6 reserved
5 (VGA) =1: screen refresh off
4 (VGA) shift load (0=4x8, 1=1x32)
3 dot clock (0=normal, 1=clock/2)
2 serial shift video load (0=4x8, 1=2x16)
1 (EGA) CRTC bandwidth (0=4/5, 1=2/5)
0 dot clocks (0=9, 1=8) (ET4000: see 06h)
SeeAlso: #P273
Bitfields for EGA/VGA sequencer map mask register:
Bit(s) Description (Table P275)
7-4 reserved
4 Genoa SuperEGA only: plane4 ???
3 write enable display memory plane 3
2 write enable display memory plane 2
1 write enable display memory plane 1
0 write enable display memory plane 0
SeeAlso: #P273
Bitfields for EGA/VGA sequencer character map select register:
Bit(s) Description (Table P276)
7-6 reserved
5 (VGA) bit3 for 2nd text-font
4 (VGA) bit3 for 1st text-font
3-2 2nd text-font (attr bit3=1)
1-0 1st text-font (attr bit3=0)
offset in font memory (4-7: VGA only)
0 00b = 0KB
0 01b = 16KB
0 10b = 32KB
0 11b = 48KB
1 00b = 8KB
1 01b = 24KB
1 10b = 40KB
1 11b = 56KB
SeeAlso: #P273
Bitfields for ET3000/ET4000 sequencer auxiliary mode:
Bit(s) Description (Table P277)
7 compatibility mode (1=VGA, 0=EGA)
6 select MCLK/2 (with bit0=0)
5 BIOS ROM address map 2
4 reserved
3 BIOS ROM address map 1
2 reserved (1)
1 select SCLK input from MCLK
0 select MCLK/4 (with bit6=1)
5+3 ROM address
00 C0000-C3FFF
01 disabled
10 C0000-C5FFF, C6800-C7FFF
11 C0000-C7FFF (default)
Notes: at least on the ET4000, this register is protected by a 'key'
this register is also supported by ET3000, but the above description
is based on the ET4000
SeeAlso: #P273
Bitfields for EGA/VGA miscellaneous output register:
Bit(s) Description (Table P278)
---Genoa SuperEGA in all emulation modes---
7-6: vertical resolution
00 (EGA) 200 lines
01 (VGA) 400 lines
10 (EGA/VGA) 350 lines
11 (VGA) 480 lines
------
7 vertical sync polarity (0=positive, 1=negative)
6 horizontal sync polarity (0=positive, 1=negative)
5 odd/even pagebit
4 EGA: 0=video driver on,
1=video driver off (feature connector used)
3-2 pixelclock
00 14/25MHz (EGA/VGA)
01 16/28Mhz (EGA/VGA)
10 (EGA/VGA) external clock (EGA)
11 (EGA/VGA) reserved
10 (Genoa SuperEGA) 39Mhz
11 (Genoa SuperEGA) 26.824Mhz
1 enable CPU RAM access
0 CRTC port address
0=3B4 mono
1=3D4 color
(color EGA: enable feature control at 3DAh,status reg 1 at 3D2h)
Bitfields for EGA/VGA indexed registers in GDC:
Bit(s) Description (Table P279)
00h set/reset register (default 00h)
functionality depending on write mode (register 05h) (see #P282)
bit7-4: reserved
bit3 : 0=write 00h, 1=write FFh in plane 3
bit2 : 0=write 00h, 1=write FFh in plane 2
bit1 : 0=write 00h, 1=write FFh in plane 1
bit0 : 0=write 00h, 1=write FFh in plane 0
01h enable set/reset register (default 00h) (see #P280)
02h color compare register (default 00h) (see #P281)
03h data rotate register (default 00h)
bit7-5: reserved
bit4-3: logical function select
00b= CPU-data overwrites
01b= CPU-data AND with latch-register
10b= CPU-data OR with latch-register
11b= CPU-data XOR with latch-register
bit2-0: rotate count
04h read map select register (default 00h)
bit7-3: reserved
bit2 : EGA?? & Genoa SuperEGA: map select bit2
bit1-0: map select (0..3)
05h mode register (see #P282)
06h miscellaneous register
bit7-4: reserved (=0)
bit3-2: memory map
00b = A0000..BFFFF (128KB)
01b = A0000..AFFFF (64KB)
10b = B0000..B7FFF (32KB)
11b = B8000..BFFFF (32KB)
bit1 : chain odd maps to even, 1=subst addess bit0
bit0 : 0=testmode, 1=graphics mode
07h color don't care register
bit7-4: reserved
bit3=1: color plane 3 don't care (ignore bit3)
bit2=1: color plane 2 don't care (ignore bit2)
bit1=1: color plane 1 don't care (ignore bit1)
bit0=1: color plane 0 don't care (ignore bit0)
08h bit mask register (default FFh)
bit7-0: bitmask for latch/databyte
(bit set=change allowed)
0Fh (Paradise SuperVGA) lock register
The ability to write and reread 00h..07h to this register
is often used as detection of Paradise chips.
bit7-0 = 01h lock/hide Paradise specific registers
= 05h unlock Paradise specific registers
bit7-3: reserved
bit2-0: flipflops, reserved
Bitfields for EGA/VGA GDC enable set/reset register:
Bit(s) Description (Table P280)
7-4 reserved (used on Genoa SuperEGA???)
3 enable set/reset plane 3
2 enable set/reset plane 2
1 enable set/reset plane 1
0 enable set/reset plane 0
3-0 0=CPU access, 1=set/reset access to plane
SeeAlso: #P279
Bitfields for EGA/VGA GDC color compare register:
Bit(s) Description (Table P281)
7-4 reserved
3 color compare 3
2 color compare 2
1 color compare 1
0 color compare 0
3-0 (color number)
SeeAlso: #P279
Bitfields for EGA/VGA GDC mode register:
Bit(s) Description (Table P282)
7 reserved
6 (VGA) 0=standard, 1=enable 256 colors
5 shift register mode, 0=standard, 1=CGA-graphics
(not used on Genoa SuperEGA???)
4=1 enable odd/even address mode
3 read mode, 0=mode0, 1=mode1
2 (EGA) test condition, 0=standard, 1=output tristate
1-0 write mode
00 mode0, plane source is CPU or set/reset
01 mode1, plane source is latch-register
10 mode2, plane source is CPU as set/reset
11 (VGA) mode3, CPU as set/reset AND bitmask
SeeAlso: #P279
(Table P283)
Values for EDSUN CEG (Continuous Edge Graphics) modes::
x: mode: colors: mix: pixel depth: effective colors:
0 = disabled 256 - 8 256
1 = A 16 16 8 1920
2 = A+REP 16 16 8 dblscn 1920
3 = A+EDP 15 16 truecolor
4 = reserved - - - -
5 = B 16 8 8 960
6 = B+REP 16 8 8 dblscn 960
7 = B+EDP 15 8 truecolor
8 = reserved - - - -
9 = C 8 8 4 224
10 = C+REP 8 8 4 dblscn 224
11 = C+EDP 7 8 truecolor
12 = reserved - - - -
13 = D 223 32 8 792096
14 = D+REP 223 32 8 dblscn 792096
15 = D+EDP 223 32 truecolor
SeeAlso: #P284
(Table P284)
Values for EDSUN CEG mixing codes:
Mode A: | Mode C:
mix: new: old: | mix: new: old: colorcode:
0 = 32/32 0/32 | 0 = - - 0
1 = 30/32 2/32 | 1 = - - 1
2 = 28/32 4/32 | 2 = - - 2
3 = 26/32 6/32 | 3 = - - 3
4 = 24/32 8/32 | 4 = - - 4
5 = 22/32 10/32 | 5 = - - 5
6 = 20/32 12/32 | 6 = - - 6
7 = 18/32 14/32 | 7 = - - 7/EDP
8 = 16/32 16/32 | 8 = 30/32 2/32 -
9 = 14/32 18/32 | 9 = 28/32 4/32 -
10 = 12/32 20/32 | 10 = 26/32 6/32 -
11 = 10/32 22/32 | 11 = 24/32 8/32 -
12 = 8/32 24/32 | 12 = 22/32 10/32 -
13 = 6/32 26/32 | 13 = 20/32 12/32 -
14 = 4/32 28/32 | 14 = 18/32 14/32 -
15 = 2/32 30/32 | 15 = 16/32 16/32 -
---Mode B: | Mode D:
mix: new: old: | mix: new: old: description:
0 = 30/32 2/32 | 00h..BEh = - - normal color
1 = 26/32 6/32 | BFh = - - EDP
2 = 22/32 10/32 | C0h = 32/32 0/32
3 = 18/32 14/32 | C1h = 31/32 1/32
4 = 14/32 18/32 | C2h = 30/32 2/32
5 = 10/32 22/32 | ... = ... ...
6 = 6/32 26/32 | DFh = 0/32 32/32
7 = 2/32 30/32 | E0h-FFh = - - normal color
SeeAlso: #P283
----------P03CE03CF--------------------------
PORT 03CE-03CF - Compaq Qvision - Functionality Level
03CE -W graphics address register (index for next port) (see #P285)
03CF RW other graphics register
(Table P285)
Values for Compaq QVision graphics register index:
0Ch RO controller version
2Fh Advanced VGA
37h early QVision 1024
71h QVision 1280 or later QVision 1024
0Dh extended controller version
0Eh extended controller capabilities
0Fh environment info
54h available memory
55h phase-locked-loop clock
56h-57h controller capabilities
----------P03D003DF--------------------------
PORT 03D0-03DF - CGA (Color Graphics Adapter)
03D0 -W same as PORT 03D4h
03D1 RW same as PORT 03D5h
03D2 -W same as PORT 03D4h
03D3 RW same as PORT 03D5h
03D4 rW CRT (6845) index register (CGA/MCGA/color EGA/color VGA)
selects which register (0-11h) is to be accessed through 03D5
this port is r/w on some VGA, e.g. ET4000
bit 7-6 =0: (VGA) reserved
bit 5 =0: (VGA) reserved for testage
bit 4-0 : selects which register is to be accessed through 03D5
03D5 -W CRT (6845) data register (CGA/MCGA/color EGA/color VGA)
selected by PORT 03D4h. registers 0C-0F may be read
(see also PORT 03B5h)
MCGA, native EGA and VGA use very different defaults from those
mentioned for the other adapters; for additional notes and
registers 00h-0Fh and EGA/VGA registers 10h-18h and ET4000
registers 32h-37h see PORT 03B5h (see #P259)
registers 10h-11h on CGA, EGA, VGA and 12h-14h on EGA, VGA are
conflictive with MCGA (see #P287)
03D6 -W same as 03D4
(under OS/2, reads return 0 if full-screen DOS session,
nonzero if windowed DOS session)
03D7 RW same as 03D5
03D8 RW CGA mode control register (except PCjr) (see #P292)
cannot be found on native color EGA, color VGA, but on most clones
03D9 RW CGA palette register (see #P294)
(MCGA) CGA border control register
Cannot be found on native EGA, VGA (without translation ROM) but
only most clones. Read access on Genoa SuperEGA is 'reset'???
03DA R- CGA status register (see #P293)
color EGA/VGA: input status 1 register
03DA -W color EGA/color VGA feature control register (see #P295)
(at PORT 03BAh w in mono mode, VGA: 3CAh r)
03DA -W HZ309 (MDA/HGC/CGA clone) card from in Heath/Zenith HZ150 PC
bit7-1=0: unknown, zero is default and known to function
properly at least in CGA modes.
bit 0 = 1 override 3x8h bit3 control register that switches
CRT beam off if bit3 is cleared. So screens always
stays on.
bit 0 = 0 3x8h bit3 indicates if CRT beam is on or off.
No more info available. Might conflict with EGA/VGA.
03DB rW clear light pen latch (not MCGA)
(R/W only with Genoa SuperEGA)
03DC RW (not MCGA) preset light pen latch
03DC -W (CGA) set light pen latch
03DD -W (MCGA) Extended mode control register
(Plantronics & Genoa SuperEGA: Plantronics ColorPlus control,
compatible with MCGA???)
(default is 00h, in mode 13h: 04h)
bit7 =1: DAC active, cannot be read
=0: DAC not active, read allowed
bit6-3 : reserved
bit2 =1: videomode 13h with 256 colors active
bit1 : reserved
bit0 =0: reserved
03DE -- (MCGA) reserved
03DE -W AT&T & color ET4000 in AT&T compatibility mode: AT&T mode control
register (see #P296)
(register enabled in ET4000, if bit7=1 in CRTC 3D4h/34h.)
03DF -- (MCGA) reserved
03DF ?W CRT/CPU page register (PCjr only)
(Table P286)
Values for EGA/VGA+ CRT Controller register index:
00h-0Fh same as MDA/CGA (see #P259)
10h R- native VGA with bit7=1 in end horizontal blanking (03h) and ET4000:
start vertical retrace
10h -W start vertical retrace
11h R- native VGA with bit7=1 in end horizontal blanking (03h):
end vertical retrace
11h -W end vertical retrace
bit7 : VGA: protection bit
=0 enable write access to 00h-07h
=1 read only regs 00h-07h with the exception
of bit4 in 07h. ET4000: protect 35h also.
bit6 : VGA: =0 three, =1 five refreshcycles/line
ET4000: reserved
bit5=0: (MCGA also) enable vertical interrupt
bit4=0: (MCGA also) clear vertical interrupt
=1: no effect
bit3-0: (MCGA also) vertical retrace end
12h vertical display end register
13h row offset register
logical screen line width in
byte mode : bytes/(line/2)
word mode : bytes/(line/4)
dword mode: bytes/(line/8)
14h underline location register
bit7=0: reserved
bit6 : VGA: 0=word-mode, 1=dword-mode (see 17h, bit6)
bit5 : VGA: 0=standard address counter clock
1=address counter clock/4 (see 17h, bit3)
bit4-0: horizontal underline row scan
15h EGA, VGA: start vertical blanking-1
16h EGA, VGA: end vertical blanking register
bit7-5 : EGA: reserved, but used on original EGA???
bit4-0 : end vertical blanking
17h EGA, VGA: mode control register (see #P262)
18h EGA, VGA: line compare register
19h Genoa SuperEGA only: double scan control
at 3B5h only in MDA, HGC emulation, but at 3D5h even in
mono EGA modes.
bit7-5 : reserved
bit4 : HR/VR width adjust flag for double scan mode
bit3-1 : 1=test, 0=normal
bit0 : double scan enable
1Bh ET3000 only: x-zoom start register
The existence of this register is often used to decide
between ET3000 and ET4000, as the ET4000 does not offer
hardware-zoom features.
1Ch ET3000 only: x-zoom end register
1Dh ET3000 only: y-zoom start register low
1Eh ET3000 only: y-zoom end register low
1Fh ET3000 only: y-zoom start & end high register
20h ET3000 only: zoom start address register low
21h ET3000 only: zoom start address register medium
23h ET3000 only: extended start address (see register 33h)
24h ET3000 only: compatibility register (see register 34h)
25h ET3000 only: overflow high register (see registers 35h, 07h)
2Dh R- S3: extended Chip ID (always 88h???)
2Eh R- S3 7xx/866/x68: new chip ID
2Fh R- S3 7xx/866/x68: chipset revision
30h RW S3: chip ID/revision (see #P302)
31h RW S3: memory configuration (see #P303)
32h ET4000: RAS/CAS configuration ('key' protected) (see #P297)
32h RW S3: backward compatibility 1 (see #P304)
33h ET4000: extended start address
This register is often used to decide between ET4000
and ET3000, when bit3-0 can be reread after write.
bit7-4 : reserved
bit3-2 : cursor address bit 17-16
bit1-0 : linear start address bits 17-16
33h RW S3: backward compatibility 2 (see #P305)
34h ET4000: 6845 compatibility control register ('key' protected)
(see #P298)
34h RW S3: backward compatibility 3 (see #P306)
35h ET4000: overflow high register (protected by 11h, bit7) (see #P299)
35h RW S3: CRT register lock (see #P307)
36h ET4000: video system configuration 1 ('key' protected) (see #P300)
36h R S3: Reset State read 1
bits 7-5: video memory size
37h ET4000: video system configuration 2 ('key' protected) (see #P301)
37h R S3: Reset State read 2
38h RW S3: S3 Register lock 1
set reg 38h to 48h and reg 39h to A5h to unlock other S3 registers
39h RW S3: S3 Register lock 2
3Ah RW S3: S3 Miscellaneous
bit 4: ???
3Bh RW S3: Data Transfer Execute position
3Ch RW S3: Interlace Retrace start
40h RW S3: "CR40" System Configuration
bit 0: enable access to 8514/A-compatible registers at PORT x2E8h
41h S3: "CR41" BIOS Flag register
42h RW S3: "CR42" mode control
43h RW S3: "CR43" extended mode
45h RW S3: "CR45" hardware graphics cursor mode
46h-47h RW S3: hardware cursor origin X
testing that register 47h can be read and written once the S3 registers
are unlocked is used as an S3 installation check
48h-49h RW S3: hardware cursor origin Y
4Ah RW S3: hardware graphics cursor foreground stack
read register 45h, then write 2 or 3 color bytes (16/24-bit color)
to specify foreground color of hardware cursor
4Bh RW S3: hardware graphics cursor background stack
read register 45h, then write 2 or 3 color bytes (16/24-bit color)
to specify background color of hardware cursor
4Ch-4Dh RW S3: hardware graphics cursor map start address
4Eh RW S3: hardware cursor pattern start X
4Fh RW S3: hardware cursor pattern start Y
50h RW S3 801+: Extended System Control 1
51h RW S3 801+: Extended System Control 2
52h RW S3 801+: Extended BIOS Flag 1
bits 7-6 are sync polarities (see #P278) for Diamond cards
53h RW S3 801+: Extended Memory Control 1 (see #P383)
54h RW S3 801+: Extended Memory Control 2
55h RW S3 801+: Extended Video DAC Control
56h RW S3 801+: External Sync Control 1
57h RW S3 801+: External Sync Control 2
58h RW S3 801+: Linear Address Window Control (see #P308)
59h RW S3 801+: Linear Address Window Position (bits 31-24)
5Ah RW S3 801+: Linear Address Window Position (bits 23-16)
Note: for memory-mapped I/O, the LAW must be on a 64M boundary
5Bh RW S3 801+: Extended BIOS Flag 2
5Ch RW S3 801+: General Output Port
bit 0: ???
bit 1: ???
bit 7: map video memory with bits 31-26 = 011111 (STB Pegasus)
5Dh RW S3 801+: Extended Horizontal Overlow
5Eh RW S3 801+: Extended Vertical Overflow
5Fh RW S3 928/964: Bus Grant Termination Position
60h RW S3 864/964: extended memory control 3
61h RW S3 864/964: extended memory control 4
62h RW S3 864/964: extended memory control 5
63h RW S3 864/964: external sync delay adjustment (high)
64h RW S3 864/964: genlocking adjustment
65h RW S3 864/964: extended miscellaneous control
66h RW S3 864/964: extended miscellaneous control 1
bit 1: reset graphics engine (Trio64)
67h RW S3 864/964: extended miscellaneous control 2 (see #P309)
68h RW S3 864/964: configuration 3
69h RW S3 864/964: extended system control 3
6Ah RW S3 864/964: extended system control 4 (bits 5-0 = offset of 64K bank)
6Bh RW S3 864/964: extended BIOS flag 3
6Ch RW S3 864/964: extended BIOS flag 4
6Dh RW S3 864/964: extended miscellaneous control
Note: registers 10h-14h on the MCGA have conflicting uses (see #P287)
SeeAlso: #P259,#P287
(Table P287)
Values for MCGA (only) CRT Controller register index:
00h-0Fh same as MDA/CGA (see #P259)
10h -W mode control register (defaults 18h, 1Ah, 19h) (see #P288)
10h R- mode control status register (see #P289)
11h -W interrupt control register (default 30h) (see #P290)
12h RW character generator/sync polarity register (see #P291)
12h R- display sense register (int. control reg [11h] bit7=1)
bit 7-2 : not used
bit 1-0 : pins 11 & 12 in monitor cable
00b = reserved
01b = analogue monochrom monitor
10b = analogue color graphics monitor
11b = no monitor
13h -W character font pointer register (see #P287)
only 00h, 10h, 20h, 30h (default 00h) are allowed here
for textmode fonts at A0000, A2000, A4000, A6000
14h -W number of characters to load during vert. retrace period (default FFh)
Note: registers 10h-14h can appear at PORT 03D5h only, not at 03B5h
SeeAlso: #P259,#P286
Bitfields for MCGA (only) CRT mode control register:
Bit(s) Description (Table P288)
7 suppress hsync/vsync
6 reserved (0)
5 reserved
4 dot clock rate
3 refresh calculations in 80x25 modes
2 reserved
1 videomode 11h active
0 videomode 13h active
SeeAlso: #P287,#P289
Bitfields for MCGA (only) CRT mode control status register:
Bit(s) Description (Table P289)
7 status bit0 CGA mode control register
6 reserved
5 clockrate 640 pixel, =0: clockrate/2 320 pixel
4 clock rate is 25,175Mhz
3 currently in textmode
2 double-scan activated
1 videomode 11h active
0 videomode 13h active
SeeAlso: #P287,#P288
Bitfields for MCGA (only) CRT interrupt control register:
Bit(s) Description (Table P290)
7 set output driver to tristate
=0: for reading of character generator reg (12h)
=1: for reading of display sense register (12h)
6 R intr generated by memory controller
5 =0 requested intr ok to handle
4 =0 free interrupt latch register
3-0 reserved
SeeAlso: #P287
Bitfields for MCGA (only) CRT character generator/sync polarity register:
Bit(s) Description (Table P291)
7 character generator active
6 =1 load codepage during display
=0 load codepage during retrace
5 codepage number (0,1)
4 512 characters active
3 reserved (0)
2 enable hsync/vsync
1 positive vsync polarity
0 positive hsync polarity
Note: default 46h in all modes, except 04h in mode 11h)
SeeAlso: #P287
Bitfields for CGA mode control register:
Bit(s) Description (Table P292)
7-0 =A0h color ET4000: second part of 'key', see Hercules compatibility
register (see PORT 03BFh) for details. For resetting the key, e.g.
write 01h to PORT 03BFh and 29h to PORT 03D8h.
7-6 not used
6 color ET4000 only, read-only: report status of bit 1 (enable 2nd page)
of hercules compatibility register (see PORT 03BFh)
5 =1 blink enabled instead of foreground high-int.
4 =1 640*200 graphics mode
3 =1 video enabled (HZ309, see PORT 03DAh bit 0)
2 =1 monochrome signal
(MCGA) in mode 6 and 11h color comes from pal-
regs 00 (black) and 07 (white), and can be
changed there.
1 =0 text mode
=1 320*200 graphics mode
0 text columns (0 = 40*25 text mode, 1 = 80*25 text mode)
SeeAlso: #P293
Bitfields for CGA status register:
Bit(s) Description (Table P293)
7-6 not used
5-4 color EGA, color ET4000: diagnose video display feedback, select
from color plane enable
3 in vertical retrace
2 (CGA,color EGA) light pen switch is off
(MCGA,color ET4000) reserved (0)
1 (CGA,color EGA) positive edge from light pen has set trigger
(MCGA,color ET4000) reserved (0)
0 horizontal retrace in progress
=0 do not use memory
=1 memory access without interfering with display
(Genoa SuperEGA) horizontal or vertical retrace
SeeAlso: #P292,#P294
Bitfields for CGA palette register:
Bit(s) Description (Table P294)
7-6 not used
5 =0 active 320x200x4 color set: red, green brown
=1 active 320x200x4 color set: cyan, magenta, white
4 intense colors in graphics, background colors text
3 intense border in 40*25, intense background in 320*200, intense
foreground in 640*200
2 red border in 40*25, red background in 320*200, red foreground in
640*200
1 green border in 40*25, green background in 320*200, green foreground
in 640*200
0 blue border in 40*25, blue background in 320*200, blue foreground in
640*200
SeeAlso: #P292,#P293
Bitfields for color EGA/VGA feature control register:
Bit(s) Description (Table P295)
7 ET4000 only: enable NMI generation ('key' protected)
6-4 not used
3 (VGA) 0 = normal vsync, 1 = vsync OR display enable
2 reserved
1 EGA and ET4000 only: FEAT1 control bit1 (pin17 feature connector)
0 EGA and ET4000 only: FEAT0 control bit0 (pin19 feature connector)
Bitfields for AT&T mode control register:
Bit(s) Description (Table P296)
7 reserved
6 underline color attribute enable
ET4000: enabled, if bit6=1 in CRTC 3D4h/34h.
5 reserved
4 reserved
3 alternate page select (=1: 2nd 16KB page, with bit0=0)
2 alternate font select (0=default font block)
1 reserved
0 double scan line mode (0=IBM 200, 1=AT&T 400 line graphics)
(ET4000) enabled, if bit7-6=11b in CRTC 3D4h/34h.
Bitfields for ET4000 RAS/CAS configuration register:
Bit(s) Description (Table P297)
7 static column memory
ET4000/W32i: interleave mode
6 RAL RAS&CAS column setup time
5 RCD RAS & CAS time
4-3 RSP, RAS pre-charge time
2 CPS, CAS pre-charge time
1-0 CSW, CAS low pulse width
SeeAlso: #P286,#P298
Bitfields for ET4000 compatibility control register:
Bit(s) Description (Table P298)
7 6845 compatibility enabled
6 ENBA enable double scan/underline in AT&T mode
5 ENXL enable translation ROM on writing
4 ENXR enable translation ROM on reading
3 ENVS VSE register port address
2 TRIS tristate ET4000 output pins
1 CS2 MCLCK clock select 2
0 EMCK enable translation of CS0 bit
SeeAlso: #P286,#P297,#P299
Bitfields for ET4000 overflow high register:
Bit(s) Description (Table P299)
7 vertical interlace mode
6 alternate RMW control
5 external sync reset (gen-lock) the line/chr counter
4 line compare bit10
3 vertical sync start bit10
2 vertical display end bit10
1 vertical total bit10
0 vertical blank start bit10
SeeAlso: #P286,#P298,#P300
Bitfields for ET4000 video system configuration 1 register:
Bit(s) Description (Table P300)
7 enable 16bit I/O read/write
6 enable 16bit display memory read/write
5 addressing mode (0=IBM, 1=TLI)
4 0=segment / 1=linear system configuration
3 font width control (1=up to 16bit, 0=8bit)
2-0 refresh count per line-1
SeeAlso: #P286,#P299,#P301
Bitfields for ET4000 video system configuration 2 register:
Bit(s) Description (Table P301)
7 DRAM display memory type (1=VRAM, 0=DRAM)
6 test (1=TLI interal test mode)
5 priority threshold control (0=more mem BW)
4 disable block read-ahead
3 display memory data depth
2 bus read data latch control
1-0 display memory data bus width
SeeAlso: #P286,#P300
(Table P302)
Values for S3 chip ID/Revision register "CR30":
81h 86c911
82h 86c911A/924
90h 86c928 (original)
...
A0h 86c801/805 A-step or B-step
...
B0h 86c928 PCI
C0h Vision864
C1h Vision864P
D0h Vision964
D1h Vision964P
E0h Trio32/64, 86c866, 86c868, 86c968; actual ID and revision stored in
PORT 03B5h registers 2Eh and 2Fh
E1h Trio32/64, 86c866, 86c868, 86c968; actual ID and revision stored in
PORT 03B5h registers 2Eh and 2Fh
SeeAlso: #P303
Bitfields for S3 "CR31" memory configuration register:
Bit(s) Description (Table P303)
0 enable base-address offset (turn on bank-switched operation)
1 two-page screen image (enables 2048-pixel wide screen)
2 VGA 16-bit memory bus (clear for 8-bit memory bus)
3 video memory above 256K accessible
5-4 display start address, bits 17&16. See also registers 51h and 69h
6 enable page-mode memory access for text-mode font access
7 (except 864/964) enable BIOS ROM address space C6800h-C7FFFh
SeeAlso: #P286,#P302,#P304
Bitfields for S3 "CR32" Backwards Compatibility 1 register:
Bit(s) Description (Table P304)
1-0 character clock period
00 IBM-compatible, 8 or 9 dots
01 7 dots
10 9 dits
2 force full character clock for horizontal timing (CGA/HGC emulation),
rather than 1/2 dot clock rate
3 backward-compatible modes (set for MDA/CGA/EGA/HGC)
4 enable hardware interrupts
6 fix VGA screen page using display start address bits 16&17 (see #P303)
7 (928,964) tri-state serial output pins SC, SOE0, and SXNR
SeeAlso: #P303,#P305
Bitfields for S3 "CR33" Backwards Compatibility 2 register:
Bit(s) Description (Table P305)
1 disable VDE protection (PORT 03D4h register 11h bit 7 will not act
on PORT 03D4h register 7h bits 1 and 6)
3 VCLK is inverted DCLK rather than inverted DCLK/2
4 disable writes to RamDAC
5 blank signal does not include border area, is same as display enable
6 lock palette/overscan registers
7 override CGA "enable video" at PORT 03D8h bit 3
SeeAlso: #P286,#P304,#P306
Bitfields for S3 "CR34" Backwards Compatibility 3 register:
Bit(s) Description (Table P306)
5 lock SR1 bit 5
7 lock PORT 03C2h bits 2,3
SeeAlso: #P305,#P307
Bitfields for S3 "CR35" Register Lock register:
Bit(s) Description (Table P307)
4 lock vertical timing registers
5 lock horizontal timing registers
SeeAlso: #P286,#P306
Bitfields for S3 "CR53" Extended Memory Control 1 register:
Bit(s) Description (Table P383)
2-1 byte swapping for linear addressing (???)
(used for big-endian addressing)
3 enable new memory-mapped I/O (Trio64V+)
4 enable memory-mapped I/O (Trio64 and Trio64V+)
5 (801/805) memory interleaving
(928) pixel multiplexing
(Trio64V+) enable memory-mapped I/O at B8000h-BFFFFh
SeeAlso: #P286
Bitfields for S3 "CR58" Linear Addressing Control register:
Bit(s) Description (Table P308)
4 enable linear addressing (see also #P361)
SeeAlso: #P306
Bitfields for S3 "CR67" Extended Miscellaneous Control 3 register:
Bit(s) Description (Table P309)
3-2 ???
7-4 ???
(values of 0000/0010/0101/0111 indicate a 16-bit pixel port)
SeeAlso: #P286,#P306
----------P03E003E1--------------------------
PORT 03E0-03E1 - OPTi 82C824 - CardBus Bridge registers
Range: PORT 03E0h or PORT 03E2h
SeeAlso: PORT 03E2h"CardBus"
03E0 ?W index for data register
03E1 RW CardBus registers
----------P03E003E8--------------------------
PORT 03E0-03E8 - LPT port address on the UniRAM card by German magazine c't
Range: selectable from 260, 2E0, 2E8, 2F0, 3E0, 3E8.
----------P03E003EF--------------------------
PORT 03E0-03EF - COM port addresses on UniRAM card by German magazine c't
Range: selectable from 238, 2E8, 2F8, 338, 3E0, 3E8, 3F8
----------P03E203E3--------------------------
PORT 03E2-03E3 - OPTi 82C824 - CardBus Bridge registers
Range: PORT 03E0h or PORT 03E2h
SeeAlso: PORT 03E0h"CardBus"
03E2 ?W index for data register
03E3 RW CardBus registers
----------P03E803EF--------------------------
PORT 03E8-03EF - serial port, same as 02E8, 02F8 and 03F8 (COM3)
SeeAlso: PORT 03F8h-03FFh
----------P03E803EF--------------------------
PORT 03E8-03EF - LPT port address on the UniRAM card by German magazine c't
Range: selectable from 260, 2E0, 2E8, 2F0, 3E0, 3E8.
----------P03EB------------------------------
PORT 03EB - GI1904 Scanner Interface Adapter
Range: PORT 022Bh, PORT 026Bh, PORT 02ABh (default), PORT 02EBh, PORT 032Bh,
PORT 036Bh, PORT 03ABh
----------P03EC------------------------------
PORT 03EC - GS-IF Scanner Interface adapter
Range: PORT 022Ch, PORT 026Ch, PORT 02ACh, PORT 02ECh (default),
PORT 032Ch, PORT 036Ch, PORT 03ACh, PORT 03ECh
Note: many SPI 400dpi/800dpi gray / H/T handy scanner by Marstek, Mustek and
others use this interface
----------P03F003F7--------------------------
PORT 03F0-03F7 - FDC 1 (1st Floppy Disk Controller) second FDC at 0370
Note: floppy disk controller is usually an 8272, 8272A, NEC765 (or
compatible), or an 82072 or 82077AA for perpendicular recording at
2.88M
SeeAlso: PORT 0370h-0377h
03F0 R- diskette controller status A (PS/2) (see #P310)
03F0 R- diskette controller status A (PS/2 model 30) (see #P311)
03F0 R- diskette EHD controller board jumper settings (82072AA) (see #P312)
03F1 R- diskette controller status B (PS/2) (see #P313)
03F1 R- diskette controller status B (PS/2 model 30) (see #P314)
03F2 -W diskette controller DOR (Digital Output Register) (see #P315)
03F3 ?W tape drive register (on the 82077AA)
bit 7-2 reserved, tri-state
bit 1-0 tape select
=00 none, drive 0 cannot be a tape drive.
=01 drive1
=10 drive2
=11 drive3
03F4 R- diskette controller main status register (see #P318)
Note: in non-DMA mode, all data transfers occur through
PORT 03F5h and the status registers (bit 5 here
indicates data read/write rather than than
command/status read/write)
03F4 -W diskette controller data rate select register (see #P319)
03F5 R- diskette command/data register 0 (ST0) (see #P320)
status register 1 (ST1) (see #P321)
status register 2 (ST2) (see #P322)
status register 3 (ST3) (see #P323)
03F5 -W diskette command register. The commands summarized here are
mostly multibyte commands. This is for brief recognition only.
(see #P326)
03F6 -- reserved on FDC
03F6 rW FIXED disk controller data register (see #P324)
03F7 RW harddisk controller (see #P325)
03F7 R- diskette controller DIR (Digital Input Register, PC/AT mode)
bit 7 = 1 diskette change
bit 6-0 tri-state on FDC
03F7 R- diskette controller DIR (Digital Input Register, PS/2 mode)
(see #P316)
03F7 R- diskette controller DIR (Digital Input Register, PS/2 model 30)
(see #P317)
03F7 -W configuration control register (PC/AT, PS/2)
bit 7-2 reserved, tri-state
bit 1-0 = 00 500 Kb/S mode (MFM)
= 01 300 Kb/S mode (MFM)
= 10 250 Kb/S mode (MFM)
= 11 1 Mb/S mode (MFM) (on 82072/82077AA)
conflict bit 0 FIXED DISK drive 0 select
03F7 -W configuration control register (PS/2 model 30)
bit 7-3 reserved, tri-state
bit 2 NOPREC (has no function. set to 0 by hardreset)
bit 1-0 = 00 500 Kb/S mode (MFM)
= 01 300 Kb/S mode (MFM)
= 10 250 Kb/S mode (MFM)
= 11 1 Mb/S mode (MFM) (on 82072/82077AA)
conflict bit 0 FIXED DISK drive 0 select
Bitfields for diskette controller status A (PS/2):
Bit(s) Description (Table P310)
7 interrupt pending
6 -DRV2 second drive installed
5 step
4 -track 0
3 head 1 select
2 -index
1 -write protect
0 +direction
SeeAlso: #P311,#P313
Bitfields for diskette controller status A (PS/2 model 30):
Bit(s) Description (Table P311)
7 interrupt pending
6 DRQ
5 step F/F
4 -track 0
3 head 1 select
2 +index
1 +write protect
0 -direction
SeeAlso: #P310,#P312,#P314
Bitfields for diskette EHD controller board jumper settings:
Bit(s) Description (Table P312)
7-6 drive 3
5-4 drive 2
3-2 drive 1
1-0 drive 0
00 1.2Mb
01 720Kb
10 2.8Mb
11 1.4Mb
SeeAlso: #P310
Bitfields for diskette controller status B (PS/2):
Bit(s) Description (Table P313)
7-6 reserved (1)
5 drive select (0=A:, 1=B:)
4 write data
3 read data
2 write enable
1 motor enable 1
0 motor enable 0
SeeAlso: #P310,#P314
Bitfields for diskette controller status B (PS/2 model 30):
Bit(s) Description (Table P314)
7 -DRV2 second drive installed
6 -DS1
5 -DS0
4 write data F/F
3 read data F/F
2 write enable F/F
1 -DS3
0 -DS2
SeeAlso: #P311,#P313
Bitfields for diskette controller Digital Output Register (DOR):
Bit(s) Description (Table P315)
7-6 reserved on PS/2
7 drive 3 motor enable
6 drive 2 motor enable
5 drive 1 motor enable
4 drive 0 motor enable
3 diskette DMA enable (reserved PS/2)
2 =1 FDC enable (controller reset)
=0 hold FDC at reset
1-0 drive select (0=A 1=B ..)
SeeAlso: #P310,#P318,#P319,#P316
Bitfields for diskette controller Digital Input Register (PS/2 mode):
Bit(s) Description (Table P316)
7 = 1 diskette change
6-3 = 1
2 datarate select1
1 datarate select0
0 = 0 high density select (500Kb/s, 1Mb/s)
0 (conflict) FIXED DISK drive 0 select
SeeAlso: #P317,#P315
Bitfields for diskette controller Digital Input Register (PS/2 model 30):
Bit(s) Description (Table P317)
7 = 0 diskette change
6-4 = 0
3 -DMA gate (value from DOR register)
2 NOPREC (value from CCR register)
1 datarate select1
0 datarate select0
0 (conflict) FIXED DISK drive 0 select
SeeAlso: #P316
Bitfields for diskette controller main status register:
Bit(s) Description (Table P318)
7 =1 RQM data register is ready
=0 no access is permitted
6 =1 transfer is from controller to system
=0 transfer is from system to controller
5 non-DMA mode
4 diskette controller is busy
3 drive 3 busy (reserved on PS/2)
2 drive 2 busy (reserved on PS/2)
1 drive 1 busy (= drive is in seek mode)
0 drive 0 busy (= drive is in seek mode)
SeeAlso: #P315
Bitfields for diskette controller data rate select register:
Bit(s) Description (Table P319)
7-2 reserved on 8272
7 software reset (self clearing) 82072/82077AA
6 power down 82072/82077AA
5 (8272/82077AA) reserved (0)
(82072) PLL select bit
4-2 write precompensation value, 000 default
1-0 data rate select
=00 500 Kb/S MFM 250 Kb/S FM
=01 300 Kb/S MFM 150 Kb/S FM
=10 250 Kb/S MFM 125 Kb/S FM
=11 1Mb/S MFM illegal FM on 8207x
SeeAlso: #P315
Bitfields for diskette command/data register 0 (ST0):
Bit(s) Description (Table P320)
7-6 last command status
00 command terminated successfully
01 command terminated abnormally
10 invalid command
11 terminated abnormally by change in ready signal
5 seek completed
4 equipment check occurred after error
3 not ready
2 head number at interrupt
1-0 unit select (0=A 1=B .. ) (on PS/2: 01=A 10=B)
SeeAlso: #P321,#P322,#P323
Bitfields for diskette status register 1 (ST1):
Bit(s) Description (Table P321)
7 end of cylinder; sector# greater then sectors/track
6 =0
5 CRC error in ID or data field
4 overrun
3 =0
2 sector ID not found
1 write protect detected during write
0 ID address mark not found
SeeAlso: #P320,#P322,#P323
Bitfields for diskette status register 2 (ST2):
Bit(s) Description (Table P322)
7 =0
6 deleted Data Address Mark detected
5 CRC error in data
4 wrong cylinder detected
3 scan command equal condition satisfied
2 scan command failed, sector not found
1 bad cylinder, ID not found
0 missing Data Address Mark
SeeAlso: #P320,#P321,#P323
Bitfields for diskette status register 3 (ST3):
Bit(s) Description (Table P323)
7 fault status signal
6 write protect status
5 ready status
4 track zero status
3 two sided status signal
2 side select (head select)
1-0 unit select (0=A 1=B .. )
SeeAlso: #P320,#P321,#P322
Bitfields for fixed disk controller data register:
Bit(s) Description (Table P324)
7-4 reserved
3 =0 reduce write current
=1 head select 3 enable
2 disk reset enable
1 disk initialization disable
0 reserved
SeeAlso: #P315,#P325
Bitfields for hard disk controller:
Bit(s) Description (Table P325)
6 FIXED DISK write gate
5 FIXED DISK head select 3 / reduced write current
4 FIXED DISK head select 2
3 FIXED DISK head select 1
2 FIXED DISK head select 0
1 FIXED DISK drive 1 select
0 FIXED DISK drive 0 select
SeeAlso: #P324
(Table P326)
Values for diskette commands:
MFM = MFM mode selected, opposite of MF mode
HDS = head select
DS = drive select
MT = multi track operation
SK = skip deleted data address mark
Command # bytes D7 6 5 4 3 2 1 0
read track 9 0 MFM 0 0 0 0 1 0
0 0 0 0 0 HDS DS1 DS0
specify 3 0 0 0 O O O 1 1
sense drive status 2 0 0 0 0 0 1 0 0
0 0 0 0 0 HDS DS1 DS0
write data 9 MT MFM 0 0 0 1 0 1
0 0 0 0 0 HDS DS1 DS0
read data 9 MT MFM SK 0 0 1 1 0
0 0 0 0 0 HDS DS1 DS0
recalibrate 2 0 0 0 0 0 1 1 1
0 0 0 0 0 0 DS1 DS0
sense interrupt status 1 0 0 0 0 1 0 0 0
write deleted data 9 MT MFM 0 0 1 0 0 1
0 0 0 0 0 HDS DS1 DS0
read ID 2 0 MFM 0 0 1 0 1 0
0 0 0 0 0 HDS DS1 DS0
read deleted data 9 MT MFM SK 0 1 1 0 0
0 0 0 0 0 HDS DS1 DS0
format track 10 0 MFM 0 0 1 1 0 1
0 0 0 0 0 HDS DS1 DS0
dumpreg ** 1 0 0 0 0 1 1 1 0
seek 3 0 0 0 0 1 1 1 1
0 0 0 0 0 HDS DS1 DS0
version ** 1 0 0 0 1 0 0 0 0
scan equal * 9 MT MFM SK 1 0 0 0 1
0 0 0 0 0 HDS DS1 DS0
perpendicular mode ** 2 0 0 0 1 0 0 1 0
0 0 0 0 0 0 WGATE GAP
configure ** 4 0 0 0 1 0 0 1 1
0 0 0 0 0 0 0 0
verify 9 MT MFM SK 1 0 1 1 0
EC 0 0 0 0 HDS DS1 DS0
scan low or equal * 9 MT MFM SK 1 1 0 0 1
0 0 0 0 0 HDS DS1 DS0
scan high or equal * 9 MT MFM SK 1 1 1 0 1
0 0 0 0 0 HDS DS1 DS0
relative seek ** 3 1 DIR 0 0 1 1 1 1
0 0 0 0 0 HDS DS1 DS0
BEWARE: not every invalid command is treated as invalid!
* Note: the scan commands aren't mentioned for the 82077AA.
** Note: EHD controller commands.
----------P03F003F1--------------------------
PORT 03F0-03F1 - PCTech RZ1000 IDE controller
Note: to unlock access to these ports instead of the standard floppy
controller status ports at these two addresses, you must perform
two immediately successive 8-bit OUTs of 55h to PORT 03F0h (there
is a fairly small time limit between the two accesses, so there
should be no other instructions between the two OUTs); after
that, values written to PORT 03F0h select the data accessed through
PORT 03F1h until an AAh is written to 03F0h
SeeAlso: #0656
03F0 ?W index port (see #P327)
03F1 RW data port
(Table P327)
Values for RZ1000 IDE controller registers:
00h ???
bit 7:
bit 1:
bit 0:
01h ???
02h ???
03h ???
04h ???
05h ???
bit 1:
AAh lock control port
----------P03F803FF--------------------------
PORT 03F8-03FF - Serial port (8250,8250A,8251,16450,16550,16550A,etc.) COM1
Range: PORT 02E8h-02EFh (COM2), PORT 02F8h-02FFh (typical non-PS/2 COM3), and
PORT 03E8h-03EFh (typical non-PS/2 COM4)
Note: chips overview:
8250 original PC, specified up to 56Kbd, but mostly runs
only 9600Bd, no scratchregister, bug: sometimes shots
ints without reasons
8250A, 16450, 16C451: ATs, most chips run up to 115KBd,
no bug: shots no causeless ints
8250B: PC,XT,AT, pseudo bug: shots one causeless int for
compatibility with 8250, runs up to 56KBd
16550, 16550N, 16550V: early PS/2, FIFO bugs
16550A,16550AF,16550AFN,16550C,16C551,16C552: PS/2, FIFO ok
82510: laptops & industry, multi emulation mode
(default=16450), special-FIFO.
8251: completely different synchronous SIO chip, not compatible!
SeeAlso: INT 14/AH=00h"SERIAL"
03F8 -W serial port, transmitter holding register (THR), which contains the
character to be sent. Bit 0 is sent first.
bit 7-0 data bits when DLAB=0 (Divisor Latch Access Bit)
03F8 R- receiver buffer register (RBR), which contains the received
character. Bit 0 is received first
bit 7-0 data bits when DLAB=0 (Divisor Latch Access Bit)
03F8 RW divisor latch low byte (DLL) when DLAB=1 (see #P328)
03F9 RW divisor latch high byte (DLM) when DLAB=1 (see #P328)
03F9 RW interrupt enable register (IER) when DLAB=0 (see #P329)
03FA R- interrupt identification register (see #P330)
Information about a pending interrupt is stored here. When the ID
register is addressed, thehighest priority interrupt is held, and
no other interrupts are acknowledged until the CPU services that
interrupt.
03FA -W 16650 FIFO Control Register (FCR) (see #P331)
03FB RW line control register (LCR) (see #P332)
03FC RW modem control register (see #P333)
03FD R- line status register (LSR) (see #P334)
03FE R- modem status register (MSR) (see #P335)
03FF RW scratch register (SCR)
(not used for serial I/O; available to any application using 16450,
16550) (not present on original 8250)
(Table P328)
Values for serial port divisor latch registers:
Some baudrates (using standard 1.8432 Mhz clock):
baudrate divisor DLM DLL
50 2304 09h 00h
75 1536 06h 00h
110 1047 04h 17h
134,5 857 03h 59h
150 768 03h 00h
300 384 01h 80h
600 192 00h C0h
1200 96 00h 60h
1800 64 00h 40h
2000 58 00h 3Ah
2400 48 00h 30h
3600 32 00h 20h
4800 24 00h 18h
7200 16 00h 10h
9600 12 00h 0Ch
19200 6 00h 06h
38400 3 00h 03h
57600 2 00h 02h
115200 1 00h 01h
Note: MIDI baudrate 32250Bd with 4Mhz quarz for c't MIDI interface
following c't 01/1991: '14400' 00h 08h
Bitfields for serial port interrupt enable register (IER):
Bit(s) Description (Table P329)
7-4 reserved (0)
3 modem-status interrupt enable
2 receiver-line-status interrupt enable
1 transmitter-holding-register empty interrupt enable
0 received-data-available interrupt enable
(also 16550(A) timeout interrupt)
Note: 16550(A) will interrupt with a timeout if data exists in the FIFO
and isn't read within the time it takes to receive four bytes or if
no data is received within the time it takes to receive four bytes
SeeAlso: #P330
Bitfields for serial port interrupt identification register (IIR):
Bit(s) Description (Table P330)
7-6 =00 reserved on 8250, 8251, 16450
=01 if FIFO queues enabled but unusable (16550 only)
=11 if FIFO queues are enabled (16550A only) (see also #P331)
6-5 (used by 82510 for FIFO status???)
5-4 reserved (0)
3 (8250,16450) reserved (0)
(16550) timeout interrupt pending
2-1 identify pending interrupt with the highest priority
11 receiver line status interrupt. priority=highest
10 received data available register interrupt. pr.=second
01 transmitter holding register empty interrupt. pr.=third
00 modem status interrupt. priority=fourth
0 =0 interrupt pending. contents of register can be used as a pointer
to the appropriate interrupt service routine
=1 no interrupt pending
Notes: interrupt pending flag uses reverse logic, 0=pending, 1=none
interrupt will occur if any of the line status bits are set
THRE bit is set when THRE register is emptied into the TSR
SeeAlso: #P329
Bitfields for serial port FIFO control register (FCR):
Bit(s) Description (Table P331)
7-6 received data available interrupt trigger level (16550)
00 1 byte
01 4 bytes
10 8 bytes
11 14 bytes
6-5 =00 (used to enable 4 byte Rx/Tx FIFOs on 82510???)
=10 ???
5-4 reserved (00)
3 change RXRDY TXRDY pins from mode 0 to mode 1
2 clear XMIT FIFO
1 clear RCVR FIFO
0 enable clear XMIT and RCVR FIFO queues
4-0 (other purpose on 82510???)
Notes: bit 0 must be set in order to write to other FCR bits
bit 1 when set the RCVR FIFO is cleared and this bit is reset
the receiver shift register is not cleared
bit 2 when set the XMIT FIFO is cleared and this bit is reset
the transmit shift register is not cleared
due to a hardware bug, 16550 FIFOs don't work correctly (this
was fixed in the 16550A)
SeeAlso: #P330
Bitfields for serial port Line Control Register (LCR):
Bit(s) Description (Table P332)
7 =1 divisor latch access bit (DLAB)
=0 receiver buffer, transmitter holding, or interrupt enable register
access
6 set break enable. serial ouput is forced to spacing state and remains
there.
5-3 PM2 PM1 PM0
x x 0 = no parity
0 0 1 = odd parity
0 1 1 = even parity
1 0 1 = high parity (sticky)
1 1 1 = low parity (sticky)
x x 1 = software parity
2 stop bit length (STB/SBL)
0 one stop bit
1 2 stop bits with (word length 6, 7, 8)
1.5 stop bits with word length 5
1-0 (WLS1-0, CL1-0)
00 word length is 5 bits
01 word length is 6 bits
10 word length is 7 bits
11 word length is 8 bits
SeeAlso: #P333,#P334,#P335
Bitfields for serial port Modem Control Register (MCR):
Bit(s) Description (Table P333)
7-5 reserved (0)
4 loopback mode for diagnostic testing of serial port
output of transmitter shift register is looped back to receiver
shift register input. In this mode, transmitted data is received
immediately so that the CPU can verify the transmit data/receive
data serial port paths.
If OUT2 is disabled, there is no official way to generate an IRQ
during loopback mode.
3 auxiliary user-designated output 2 (OUT2)
because of external circuity OUT2 must be 1 to master-intr-enableing.
BUG: Some Toshiba Laptops utilize this bit vice versa, newer Toshiba
machines allow assignment of the bit's polarity in system setup.
82050: This bit is only effective, if the chip is being used with an
externally-generated clock.
2 =1/0 auxiliary user-designated output 1 (OUT1)
should generally be cleared!!
Some external hardware, e.g. c't MIDI interface (and compatibles) use
this bit to change the 8250 input clock from 1,8432 MHz to 4Mhz
(enabling MIDI-conformant baudrates) and switching to
MIDI-compatible current loop connectors.
1 force request-to-send active (RTS)
0 force data-terminal-ready active (DTR)
SeeAlso: #P332,#P334,#P335
Bitfields for serial port Line Status Register (LSR):
Bit(s) Description (Table P334)
7 =0 reserved
=1 on some chips produced by UMC
6 transmitter shift and holding registers empty
5 transmitter holding register empty (THRE)
Controller is ready to accept a new character to send.
4 break interrupt. the received data input is held in the zero bit
state longer than the time of start bit + data bits + parity bit +
stop bits.
3 framing error (FE). the stop bit that follows the last parity or data
bit is a zero bit
2 parity error (PE). Character has wrong parity
1 overrun error (OE). a character was sent to the receiver buffer
before the previous character in the buffer could be read. This
destroys the previous character.
0 data ready. a complete incoming character has been received and sent
to the receiver buffer register.
SeeAlso: #P332,#P333,#P335
Bitfields for serial port Modem Status Register (MSR):
Bit(s) Description (Table P335)
7 data carrier detect (-DCD)
6 ring indicator (-RI)
5 data set ready (-DSR)
4 clear to send (-CTS)
3 delta data carrier detect (DDCD)
2 trailing edge ring indicator (TERI)
1 delta data set ready (DDSR)
0 delta clear to send (DCTS)
Notes: bits 0-3 are reset when the CPU reads the MSR
bit 4 is the Modem Control Register RTS during loopback test
bit 5 is the Modem Control Register DTR during loopback test
bit 6 is the Modem Control Register OUT1 during loopback test
bit 7 is the Modem Control Register OUT2 during loopback test
SeeAlso: #P332,#P333,#P334
--------!---Note-----------------------------
Note: Adresses above 03FF generally apply to EISA and PCI machines only !
EISA port assignments:
1000-1FFF slot 1 EISA
2000-2FFF slot 2 EISA
3000-3FFF slot 3 EISA
4000-4FFF slot 4 EISA
5000-5FFF slot 5 EISA
6000-6FFF slot 6 EISA
7000-7FFF slot 7 EISA
----------P0401040B--------------------------
PORT 0401-040B - EISA DMA Controller
SeeAlso: PORT 0481h-048Bh"EISA",PORT 04D4h-04D6h"EISA"
0401 RW DMA channel 0 word count byte 2 (high)
0403 RW DMA channel 1 word count byte 2 (high)
0405 RW DMA channel 2 word count byte 2 (high)
0407 RW DMA channel 3 word count byte 2 (high)
040A -W extended DMA chaining mode register, channels 0-3 (see #P336)
040A R- channel interrupt (IRQ13) status register (see #P337)
040B -W DMA extended mode register for channels 0-3 (see #P338)
(bit settings same as PORT 04D6h)
Bitfields for EISA extended DMA chaining mode register (channels 0-3):
Bit(s) Description (Table P336)
7-5 reserved
4 =0 generate IRQ13
=1 generate terminal count
3 =0 do not start chaining
=1 programming complete
2 =0 disable buffer chaining mode (default)
=1 enable buffer chaining mode
1-0 DMA channel select
SeeAlso: #P337,#P338,#P345
Bitfields for EISA channel interrupt (IRQ13) status register:
Bit(s) Description (Table P337)
7-5 interrupt on channels 7-5
4 reserved
3-0 interrupt on channels 3-0
SeeAlso: #P336
Bitfields for EISA DMA extended mode register (channels 0-3):
Bit(s) Description (Table P338)
7 =0 enable stop register
6 =0 terminal count is an output for this channel (default)
5-4 DMA cycle timing
00 ISA-compatible (default)
01 type A timing mode
10 type B timing mode
11 burst DMA mode
3-2 Address mode
00 8-bit I/O, count by bytes (default)
01 16-bit I/O, count by words, address shifted
10 32-bit I/O, count by bytes
11 16-bit I/O, count by bytes
1-0 DMA channel select
SeeAlso: #P336,#P346
----------P040A043F--------------------------
PORT 040A-043F - Intel 82378ZB embedded DMA controller
Range: relocatable via Relocation Base Address register (see #0871)
SeeAlso: PORT 0401h"EISA",#0860,#0871
040A R- scatter/gather interrupt status (see #P339)
040B -W DMA1 extended mode
0410 -W CH0 scatter/gather command (see #P340)
0411 -W CH1 scatter/gather command
0412 -W CH2 scatter/gather command
0413 -W CH3 scatter/gather command
0414 -W CH4 scatter/gather command
0415 -W CH5 scatter/gather command
0416 -W CH6 scatter/gather command
0417 -W CH7 scatter/gather command (see #P340)
0418 R- CH0 scatter/gather status (see #P341)
0419 R- CH1 scatter/gather status
041A R- CH2 scatter/gather status
041B R- CH3 scatter/gather status
041C R- CH4 scatter/gather status
041D R- CH5 scatter/gather status
041E R- CH6 scatter/gather status
041F R- CH7 scatter/gather status (see #P341)
0420d RW CH0 scatter/gather descriptor table address
0424d RW CH1 scatter/gather descriptor table address
0428d RW CH2 scatter/gather descriptor table address
042Cd RW CH3 scatter/gather descriptor table address
0430d RW CH4 scatter/gather descriptor table address
0434d RW CH5 scatter/gather descriptor table address
0438d RW CH6 scatter/gather descriptor table address
043Cd RW CH7 scatter/gather descriptor table address
(Table P339)
Call Intel 82378ZB Scatter/Gather Interrupt Status Register with:
7 channel 7 has interrupt due to S/G transfer
...
0 channel 0 has interrupt due to S/G transfer
SeeAlso: #P340,#P341
Bitfields for Intel 82378ZB Scatter/Gather Command Register:
Bit(s) Description (Table P340)
7 select last-buffer termination type
=0 assert IRQ13 on completion
=1 assert EOP on completion
6 enable bit 7 termination-type selection
5-2 reserved (0)
1-0 scatter-gather command
00 none
01 start S/G command
10 stop S/G command
11 reserved
SeeAlso: #P339,#P341,#0871
Bitfields for Intel 82378ZB Scatter/Gather Status Register:
Bit(s) Description (Table P341)
7 no next link
6 reserved
5 issue IRQ13 instead of EOP at end of last buffer
4 reserved
3 scatter/gather Base Register status
=1 buffer link has been loaded
=0 empty
2 scatter/gather Current Register status
=1 buffer link has been loaded
=0 empty
1 reserved
0 scatter/gather is active
SeeAlso: #P340
--------X-P040D040F--------------------------
PORT 040D-040F - EISA - Intel 82357
040D R- chip stepping level
040E RW test register 1
040F RW test register 2
----------P04610462--------------------------
PORT 0461-0462 - EISA NMI CONTROL
0461 RW Extended NMI status/control register (see #P342)
0462 -W Software NMI register. writing to this register causes an NMI if
NMIs are enabled
bit 7 = 1 generates an NMI
Bitfields for EISA extended NMI status control register:
Bit(s) Description (Table P342)
7 R- NMI pending from fail-safe (watchdog) timer
6 R- NMI pending from bus timeout NMI status
5 R- NMI pending from I/O port status
4 R- busmaster preemption timeout if bit 6 set
3 RW bus timeout NMI enable
2 RW fail-safe (watchdog) NMI enable
1 RW NMI I/O port enable
0 RW RSTDRV. bus reset
=0 NORMAL bus reset operation
=1 reset bus asserted
--------X-P04640465--------------------------
PORT 0464-0465 - EISA BUS MASTER STATUS
0464w R bus master status latch register (slots 1-16)
identifies the last bus master that had control of the bus (bit N =0 if
slot N+1 had control last)
----------P0481048B--------------------------
PORT 0481-048B - EISA DMA page registers
Note: these registers are also supported on many non-EISA machines, e.g. by
most machines using Intel PCI chipsets
SeeAlso: PORT 0401h-040Bh"EISA",PORT 04C6h-04CFh"EISA"
0481 RW DMA channel 2 address byte 3 (high)
0482 RW DMA channel 3 address byte 3 (high)
0483 RW DMA channel 1 address byte 3 (high)
0487 RW DMA channel 0 address byte 3 (high)
0489 RW DMA channel 6 address byte 3 (high)
048A RW DMA channel 7 address byte 3 (high)
048B RW DMA channel 5 address byte 3 (high)
----------P04C604CF--------------------------
PORT 04C6-04CF - EISA DMA count registers
SeeAlso: PORT 0401h-040Bh"EISA",PORT 0481h-048Bh"EISA",PORT 04E0h-04FFh"EISA"
04C6 RW DMA channel 5 word count byte 2 (high)
04CA RW DMA channel 6 word count byte 2 (high)
04CE RW DMA channel 7 word count byte 2 (high)
--------X-P04D004D1--------------------------
PORT 04D0-04D1 - EISA IRQ control
Note: these registers are also supported on many non-EISA machines, e.g. by
most machines using Intel PCI chipsets
SeeAlso: PORT 04D4h-040Bh"EISA"
04D0 -W IRQ 0-7 interrupt edge/level registers (see #P343)
04D1 -W IRQ 8-15 interrupt edge/level registers (see #P344)
Bitfields for EISA IRQ 0-7 interrupt edge/level register:
Bit(s) Description (Table P343)
7 IRQ 7 is level sensitive
6 IRQ 6 is level sensitive
5 IRQ 5 is level sensitive
4 IRQ 4 is level sensitive
3 IRQ 3 is level sensitive
2-0 reserved
SeeAlso: #P344
Bitfields for EISA IRQ 8-15 interrupt edge/level register:
Bit(s) Description (Table P344)
7 IRQ 15 is level sensitive
6 IRQ 14 is level sensitive
5 reserved (1)
4 IRQ 12 is level sensitive
3 IRQ 11 is level sensitive
2 IRQ 10 is level sensitive
1 IRQ 9 is level sensitive
0 reserved
SeeAlso: #P343
----------P04D404D6--------------------------
PORT 04D4-04D6 - EISA DMA control
Note: PORT 04D6h is also supported by the Intel 82378ZB System I/O controller
SeeAlso: PORT 0401h-040Bh"EISA",PORT 04D0h-04D1h"EISA"
04D4 R- DMA chaining status
04D4 -W extended DMA chaining mode register, channels 4-7 (see #P345)
04D6 -W DMA extended mode register for channels 4-7 (see #P346)
bit settings same as PORT 040Bh
Bitfields for EISA extended DMA chaining mode register (channels 4-7):
Bit(s) Description (Table P345)
7-5 reserved (0)
4 =0 generate IRQ 13
=1 generate terminal count
3 =0 do not start chaining
=1 programming complete
2 =0 disable buffer chaining mode (default)
=1 enable buffer chaining mode
1-0 DMA channel select
SeeAlso: #P336,#P346
Bitfields for EISA DMA extended mode register (channels 4-7):
Bit(s) Description (Table P346)
7 =0 enable stop register
6 =0 terminal count is an output for this channel (default)
5-4 DMA cycle timing
00 ISA-compatible (default)
01 type A timing mode
10 type B timing mode
11 burst DMA mode
3-2 Address mode
00 8-bit I/O, count by bytes (default)
01 16-bit I/O, count by words, address shifted
10 32-bit I/O, count by bytes
11 16-bit I/O, count by bytes
1-0 DMA channel select
SeeAlso: #P338,#P345
----------P04E004FF--------------------------
PORT 04E0-04FF - EISA DMA stop registers
SeeAlso: PORT 0481h-048Bh"EISA"
04E0-04E2 RW channel 0 stops if DMA transfer reaches specified address
04E4-04E6 RW channel 1
04E8-04EA RW channel 2
04EC-04EE RW channel 3
04F4-04F6 RW channel 5
04F8-04FA RW channel 6
04FC-04FE RW channel 7
----------P05300533--------------------------
PORT 0530-0533 - Gravis Ultra Sound Daughter Card by Advanced Gravis
Range: dipswitch selectable from PORT 0530h-0533h, PORT 0604h-0607h,
PORT 0E80h-0E83h, and PORT 0F40h-0F43h
0530 RW address select
0531 RW data
0532 RW status
0533 RW PIO
----------P05300537--------------------------
PORT 0530-0537 - Windows Sound System (default address)
Range: dipswitch selectable among PORT 0530h-0537h,PORT 0604h-060Bh,
PORT 0E80h-0E87h, and PORT 0F40h-0F47h
Notes: the Sound Galaxy NX16 sound cards contains a Crystal CS4231, and thus
support the CODEC portion of the WSS on ports 0534h-0537h
(or 0608h-060Bh, etc.)
the AMD InterWave chip supports a superset of the WSS CS4231 Codec,
though by default it is not placed at any of the addresses used by
the WSS
0534 ?W register select (index) (see #P347)
0535 RW data register (selected by PORT 0534h)
(Table P347)
Values for Windows Sound System CS4231 Codec register number:
00h Mixer: ADC volume (left)
01h Mixer: ADC volume (right)
02h Mixer: Line In volume (right) (see #P348)
03h Mixer: Line In volume (left) (see #P348)
04h Mixer: FM volume (right) (see #P348)
05h Mixer: FM volume (left) (see #P348)
06h Mixer: playback DAC volume (left)
07h Mixer: playback DAC volume (right)
08h playback data format
09h configuration register 1
0Ah external control
0Bh Codec status register 2
0Ch mode select
bit 6: ???
0Dh loopback control
(Sound Galaxy) microphone input enabled by bit 0 ???
0Eh playback count (high)
0Fh playback count (low)
10h configuration register 2
11h configuration register 3
12h Mixer: CD volume (right) (see #P348)
13h Mixer: CD volume (left) (see #P348)
14h timer (low)
15h timer (high)
16h Mixer: microphone input control (left)
17h Mixer: microphone input control (right)
18h Codec status register 3
19h Mixer: output attenuation (left)
1Ah mono input/output control
(Sound Galaxy) SB volume (see #P349)
1Bh Mixer: output attenuation (right)
1Ch record data format
1Dh playback variable frequency
1Eh record count (high)
1Fh record count (low)
48h (Sound Galaxy) ???
Notes: to enable the microphone input on the Sound Galaxy, ALL of the
following registers must be set: 00h set to 80h, 01h set to 80h,
07h to 00h, 0Dh to 01h, and 48h to 4Bh
on the Sound Galaxy NX16, only bits 0-4 of the register number are
fully decoded, so most registers above 1Fh are aliases of the
first 32 registers
Bitfields for WSS mixer volume:
Bit(s) Description (Table P348)
7 disable input source
6-5 reserved???
4-0 volume (00h = highest, 1Fh = lowest)
SeeAlso: #P347,#P349
Note: the GW2000 GWBVOL.EXE only permits the setting of volume levels
08h (reported as 16) to 18h (reported as 0, and sets bit 7 as well)
Bitfields for WSS mixer volume (SoundBlaster):
Bit(s) Description (Table P349)
7 disable input source
6-4 reserved???
3-0 volume (00h = highest, 0Fh = lowest)
SeeAlso: #P347,#P348
----------P0601------------------------------
PORT 0601 - Headland HL21, Acer M5105 chipsets - SYSTEM CONTROL
0601 -W system control (see #P350)
0601 R- status (see #P351)
Bitfields for Headland HL21/Acer M5105 system control register:
Bit(s) Description (Table P350)
7 =1 power LED on
6 =1 LCD backlight off
5 ???
4 ???
3 ???
2 =1 video chips disabled, screen blanked.
1 ???
0 =1 will lock up your machine!
SeeAlso: #P351
Bitfields for Headland HL21/Acer M5105 status register:
Bit(s) Description (Table P351)
7 =0 if screen enabled always these values
6 =0
5 =0
4 =0
3 =0
2 =1 (=0 at low power)
1 =0 power OK
0 =0
SeeAlso: #P350
----------P06040607--------------------------
PORT 0604-0607 - Gravis Ultra Sound Daughter Card by Advanced Gravis
Range: dipswitch selectable from PORT 0530h-0533h, PORT 0604h-0607h,
PORT 0E80h-0E83h, and PORT 0F40h-0F43h
----------P0604060B--------------------------
PORT 0604-060B - Windows Sound System
Range: PORT 0530h-0537h,PORT 0604h-060Bh,PORT 0E80h-0E87h,PORT 0F40h-0F47h
SeeAlso: PORT 0530h"Sound System"
----------P06200627--------------------------
PORT 0620-0627 - PC network (adapter 1)
0628-062F - PC network (adapter 2)
----------P06800681--------------------------
PORT 0680-0681 - Microchannel POST Diagnostic (write only)
0680 -W Microchannel POST Diagnostic
0681 -W secondary MCA POST diagnostic
----------P06A006A8--------------------------
PORT 06A0-06A8 - non-standard COM port addresses
Range: selectable from 0280, 0288, 0290, 0298, 06A0, 06A8
Note: V20-XT by German magazine c't
----------P06A806AF--------------------------
PORT 06A8-06AF - non-standard COM port addresses
Range: selectable from 0280, 0288, 0290, 0298, 06A0, 06A8
Note: V20-XT by German magazine c't
----------P06E206E3--------------------------
PORT 06E2-06E3 - data aquisition (adapter 1)
----------P06E8------------------------------
PORT 06E8 - S3 86C928 video controller (ELSA Winner 1000)
----------P06E806EF--------------------------
PORT 06E8-06EF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
SeeAlso: PORT 02E8h-02EFh,PORT 0AE8h,PORT 96E8h,PORT 9AE8h
06E8w -W CRT control: horizontal displayed
----------P0746------------------------------
PORT 0746 - Gravis Ultra Sound by Advanced Gravis - BOARD VERSION / MIXER
SeeAlso: PORT 0240h-024Fh,PORT 0340h-034Fh
0746 R- board version (rev 3.7+)
FFh Pre 3.6 boards, ICS mixer NOT present
05h Rev 3.7 with ICS Mixer. Some R/L: flip problems.
06h-09h Revision 3.7 and above. ICS Mixer present
0Ah- UltraMax. CS4231 present, no ICS mixer
0746 -W Mixer Control Port
----------P07900793--------------------------
PORT 0790-0793 - cluster (adapter 1)
----------P080008FF--------------------------
PORT 0800-08FF - I/O port access registers for extended CMOS RAM or SRAM
(256 bytes at a time)
Note: sometimes plain text can be seen here
--------X-P080008FF--------------------------
PORT 0800-08FF - reserved for EISA system motherboard
----------P0A200A23--------------------------
PORT 0A20-0A23 - Token Ring (adapter 1)
0A24-0A27 - Token Ring (adapter 2)
----------P0A79------------------------------
PORT 0A79 - Plug-and-Play - WRITE DATA PORT
Desc: all data written to the Plug-and-Play configuration registers is
written to this port, including the configuration byte which
indicates the I/O port from which data is to be read when reading
the configuration registers
SeeAlso: PORT 0279h
0A79 -W Plug-and-Play data writes
----------P0AE20AE3--------------------------
PORT 0AE2-0AE3 - cluster (adapter 2)
----------P0AE8------------------------------
PORT 0AE8 - S3 86C928 video controller (ELSA Winner 1000)
----------P0AE80AEF--------------------------
PORT 0AE8-0AEF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
0AE8w -W CRT control: horizontal sync start
----------P0B900B93--------------------------
PORT 0B90-0B93 - cluster (adapter 2)
----------P0C00------------------------------
PORT 0C00 - EISA??? - PAGE REGISTER
0C00 RW page register to write to SRAM or I/O
--------X-P0C000CFF--------------------------
PORT 0C00-0CFF - reserved for EISA system motherboard
----------P0C7C------------------------------
PORT 0C7C bit 7-4 (Compaq)
--------X-P0C800C83--------------------------
PORT 0C80-0C83 - EISA system board ID registers
0C80 R- bit 7: unused (0)
bits 6-2: manufacturer ID, first compressed ASCII char
bits 1-0: manufacturer ID, second compressed ASCII char (high)
0C81 R- bits 7-5: manufacturer ID, second compressed ASCII char (low)
bits 4-0: manufacturer ID, third compressed ASCII char
0C82 R- reserved for manufacturer's use
0C83 R- bits 7-3: reserved for manufacturer's use
bits 2-0: EISA bus version
--------X-P0CF80CFF--------------------------
PORT 0CF8-0CFF - PCI Configuration Mechanism 1 - Configuration Registers
SeeAlso: PORT 0CF8h"Mechanism 2"
0CF8d -W configuration address port (see #P352)
0CFCd RW configuration data port (when PORT 0CF8h bit 31 is set)
Bitfields for PCI configuration address port:
Bit(s) Description (Table P352)
1-0 reserved (00)
7-2 configuration register number (see #0798)
10-8 function
15-11 device number
23-16 bus number
30-24 reserved (0)
31 enable configuration space mapping
Note: configuration registers are considered DWORDs, so the number in bits
7-2 is the configuration space address shifted right two bits
SeeAlso: #P353
--------X-P0CF80CFA--------------------------
PORT 0CF8-0CFA - PCI Configuration Mechanism 2 - Configuration Registers
Notes: this configuration mechanism is deprecated as of PCI version 2.1;
only mechanism 1 should be used for new systems
to access the configuration space, write the target bus number to
the Forward Register, then write to the Configuration Space
Enable register, and finally read or write the appropriate I/O
port(s) in the range C000h to CFFFh (where Cxrrh accesses location
'rr' in physical device 'x's configuration data)
the Intel "Saturn" and "Neptune" chipsets use configuration mechanism 2
SeeAlso: PORT 0CF8h"Mechanism 1",PORT C000h"PCI Configuration",PORT 0CFBh
0CF8 RW Configuration Space Enable (CSE) (see #P353)
0CFA RW Forward Register (selects target bus number)
Bitfields for PCI Configuration Space Enable:
Bit(s) Description (Table P353)
0 Special Cycle Enable (SCE)
3-1 target function number (PCI logical device within physical device)
7-4 key (non-zero to allow configuration)
SeeAlso: #P352
----------P0CF9------------------------------
PORT 0CF9 - Intel chipsets - TURBO/RESET CONTROL REGISTER
Notes: this port can only be accessed via 8-bit IN or OUT instructions by
the CPU
supported by the Intel "Saturn" and "Neptune" (82434NX) chipsets,
the Intel 82454KX/GX (450GX chipset), Intel 82420EX chipset, etc.
SeeAlso: PORT C051h,#0851,#0937
0CF9 RW reboot system, optionally selecting de-turbo mode (see #P354)
Bitfields for Intel 82420EX turbo/reset control register:
Bit(s) Description (Table P354)
7-4 reserved (0)
3 (450KX/GX only) enable CPU BIST on reset
2 reset CPU
1 reset mode
0 soft reset
1 hard reset
0 deturbo mode
Note: when resetting the CPU, two writes are required: the first sets the
state of bit 1 while keeping bit 2 cleared, and the second sets
bit 2; the reset occurs on bit 2's transition from 0 to 1.
SeeAlso: PORT C051h
----------P0CFB------------------------------
PORT 0CFB - Intel 82434NX (Neptune) - PCI MECHANISM CONTROL REGISTER
Note: not present on the 82434LX (Mercury), which supports only mechanism #2
SeeAlso: PORT 0CF8h
0CFB RW specify which PCI access mechanism is to be enabled
Bitfields for Intel 82434NX PCI mechanism control register:
Bit(s) Description (Table P355)
7-1 reserved
0 PCI Configuration Access Mechanism Select
=0 use PCI configuration access mechanism #2 (0CF8/0CFA) (default)
=1 use PCI configuration access mechanism #1 (0CF8/0CFC)
--------s-P0E800E83--------------------------
PORT 0E80-0E83 - Gravis Ultra Sound Daughter Card by Advanced Gravis
Range: dipswitch selectable from PORT 0530h-0533h, PORT 0604h-0607h,
PORT 0E80h-0E83h, and PORT 0F40h-0F43h
--------s-P0E800E87--------------------------
PORT 0E80-0E87 - Windows Sound System
Range: PORT 0530h-0537h,PORT 0604h-060Bh,PORT 0E80h-0E87h,PORT 0F40h-0F47h
SeeAlso: PORT 0530h"Sound System"
--------V-P0EE8------------------------------
PORT 0EE8 - S3 86C928 video controller (ELSA Winner 1000)
--------V-P0EE80EEF--------------------------
PORT 0EE8-0EEF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
0EE8w -W CRT control: horizontal sync width
--------s-P0F400F43--------------------------
PORT 0F40-0F43 - Gravis Ultra Sound Daughter Card by Advanced Gravis
Range: dipswitch selectable from PORT 0530h-0533h, PORT 0604h-0607h,
PORT 0E80h-0E83h, and PORT 0F40h-0F43h
--------s-P0F400F47--------------------------
PORT 0F40-0F47 - Windows Sound System
Range: PORT 0530h-0537h,PORT 0604h-060Bh,PORT 0E80h-0E87h,PORT 0F40h-0F47h
SeeAlso: PORT 0530h"Sound System"
--------s-P0F8D------------------------------
PORT 0F8D - OPTi 82C750 (Vendetta) - AUDIO MODULE BASE ADDRESS REGISTER
--------X-P100010FF--------------------------
PORT 1000-10FF - available for EISA slot 1
----------P12E812EF--------------------------
PORT 12E8-12EF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
12E8w -W CRT control: vertical total
--------V-P12EE------------------------------
PORT 12EE - ATI Mach32 - CONFIGURATION STATUS 0
SeeAlso: PORT 16EEh"Mach32",PORT 42EEh"Mach32",PORT 52EEh"Mach32"
----------P13901393--------------------------
PORT 1390-1393 - cluster (adapter 3)
----------P13C6------------------------------
PORT 13C6 - Compaq - ???
Note: this port is read by the Compaq MS-DOS 4.0/5.0 CHARSET utility
13C6 R? Compaq video status??? (see #P384)
Bitfields for Compaq video status???:
Bit(s) Description (Table P384)
7 ???
6 flag
5-3 ???
2-0 status of display???
--------X-P140014FF--------------------------
PORT 1400-14FF - available for EISA slot 1
----------P16E816EF--------------------------
PORT 16E8-16EF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
16E8w -W CRT control: vertical displayed
--------V-P16EE------------------------------
PORT 16EE - ATI Mach32 - CONFIGURATION STATUS 1
SeeAlso: PORT 12EEh"Mach32",PORT 42EEh"Mach32",PORT 52EEh"Mach32"
--------X-P180018FF--------------------------
PORT 1800-18FF - available for EISA slot 1
----------P1AE81AEF--------------------------
PORT 1AE8-1AEF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
1AE8w -W CRT control: vertical sync start
--------X-P1C001CFF--------------------------
PORT 1C00-1CFF - available for EISA slot 1
----------P1C65------------------------------
PORT 1C65 - Compaq Contura Aero
SeeAlso: PORT 2065h
1C65 R? bit 6: operating on battery power
--------X-P1C801C8F--------------------------
PORT 1C80-1C8F - VESA XGA Video in EISA slot 1
1C80-1C83 RW EISA Video ID
1C84 RW EISA Video expansion board control (see #P356)
1C85 RW EISA Setup control
1C88 RW EISA Video Programmable Option Select 0
1C89-1C8F RW EISA Video Programmable Option Select 1-7
--------X-P1C801C83--------------------------
PORT 1C80-1C83 - EISA board product ID (board in slot 1)
1C80 R? bit 7: unused (0)
bits 6-2: manufacturer ID, first compressed ASCII char
bits 1-0: manufacturer ID, second compressed ASCII char (high)
1C81 R? bits 7-5: manufacturer ID, second compressed ASCII char (low)
bits 4-0: manufacturer ID, third compressed ASCII char
1C82 R? bits 7-4: first hex digit of product type
bits 3-0: second hex digit of product type
1C83 R? bits 7-4: third hex digit of product type
bits 3-0: product revision number (hex digit)
--------X-P1C84------------------------------
PORT 1C84 - EISA CONFIGURATION FLAGS (board in slot 1)
1C84 RW configuration flags (see #P356)
Bitfields for EISA Add-in Card configuration flags:
Bit(s) Description (Table P356)
0 enable
1 IOCHKERR (read-only) card is generating CHCHK#, causing an NMI
2 IOCHKRST reset card
7-3 card-specific
--------X-P1C85------------------------------
PORT 1C85 - EISA SETUP CONTROL (board in slot 1)
--------V-P1C85------------------------------
PORT 1C85 - Compaq Qvision EISA - Virtual Controller ID
--------X-P1C881C8F--------------------------
PORT 1C88-1C8F - EISA PROGRAMMABLE OPTION SELECT (board in slot 1)
--------V-P1EE81EEF--------------------------
PORT 1EE8-1EEF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
1EE8w -W CRT control: vertical sync width
--------V-P1EEC------------------------------
PORT 1EEC - Mach64 - ???
1EEC RW display power and other controls
bits 3-2: DPMS power mode
00 normal
01 standby
10 suspend
11 off
--------X-P200020FF--------------------------
PORT 2000-20FF - available for EISA slot 2
----------P2065------------------------------
PORT 2065 - Compaq Contura Aero
SeeAlso: PORT 1C65h"Compaq",PORT 2465h"Compaq"
2065 -W ??? (84h seen)
--------V-P2100------------------------------
PORT 2100 - XGA Video Operating Mode Register
Note: this port is for the first XGA in the system; 2110-2170 are used for
the second through eighth XGAs
--------V-P2101------------------------------
PORT 2101 - XGA Video Aperture Control
Note: this port is for the first XGA in the system; 2111-2171 are used for
the second through eighth XGAs
--------V-P21022103--------------------------
PORT 2102-2103 - XGA ???
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2104------------------------------
PORT 2104 - XGA Video Interrupt Enable
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2105------------------------------
PORT 2105 - XGA Video Interrupt Status
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2106------------------------------
PORT 2106 - XGA Video Virtual Memory Control
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2107------------------------------
PORT 2107 - XGA Video Virtual Memory Interrupt Status
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2108------------------------------
PORT 2108 - XGA Video Aperture Index
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P2109------------------------------
PORT 2109 - XGA Video Memory Access Mode
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P210A------------------------------
PORT 210A - XGA Video Index for Data
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P210B------------------------------
PORT 210B - XGA Video Data (byte)
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
--------V-P210C210F--------------------------
PORT 210C-210F - XGA Video Data (word/dword)
Note: this port is for the first XGA in the system; 211x-217x are used for
the second through eighth XGAs
210C RW byte data
210Cw RW word data
210Cd RW dword data
--------V-P2110211F--------------------------
PORT 2110-211F - IBM XGA (eXtended Graphics Adapter 8514/A) (second installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2120212F--------------------------
PORT 2120-212F - IBM XGA (eXtended Graphics Adapter 8514/A) (third installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2130213F--------------------------
PORT 2130-213F - IBM XGA (eXtended Graphics Adapter 8514/A) (fourth installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2140214F--------------------------
PORT 2140-214F - IBM XGA (eXtended Graphics Adapter 8514/A) (fifth installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2150215F--------------------------
PORT 2150-215F - IBM XGA (eXtended Graphics Adapter 8514/A) (sixth installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2160216F--------------------------
PORT 2160-216F - IBM XGA (eXtended Graphics Adapter 8514/A) (seventh installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P2170217F--------------------------
PORT 2170-217F - IBM XGA (eXtended Graphics Adapter 8514/A) (eighth installed)
Notes: see individual 210x entries above
c't says default instance number is 6, i.e. addresses 216x
--------V-P217A217B--------------------------
PORT 217A-217B - ET4000/W32 CRTC-B/Sprite
Note: Alternative addresses may depend on adapter manufacturer,
Tseng claims 21xA with x=three address bits, selected by IOD2..0
during power up reset.
21xA RW ET4000/W32(i) CRTC-B/Sprite index register
bit7-0: index
21xB RW ET4000/W32(i) CRTC-B/Sprite data register (see #P357)
(Table P357)
Values for ET4000/W32(i) CRTC-B/Sprite data register index:
E0h CRTC-B / Sprite Horizontal Pixel Position, Low
bit7-0: horizontal pixel position bit7-0
E1h CRTC-B / Sprite Horizontal Pixel Position, High
bit7-4: reserved
bit3-0: horizontal pixel position bit11-8
E2h CRTC-B Width Low / Sprite Horizontal Preset
bit7-0: width of CRTC-B bit7-0
bit5-0: horizontal preset for sprite
E3h CRTC-B Width High / Sprite Horizontal Preset
bit7-4: reserved
bit3-0: width of CRTC-B bit11-8
E4h CRTC-B / Sprite Vertical Pixel Position, Low
bit7-0: vertical pixel position bit7-0
E5h CRTC-B / Sprite Vertical Pixel Position, High
bit7-4: reserved
bit3-0: vertical pixel position bit11-8
E6h CRTC-B Height Low / Sprite Vertical Preset
bit7-0: height of CRTC-B bit7-0
bit5-0: vertical preset for sprite
E7h CRTC-B Height High / Sprite Vertical Preset
bit7-4: reserved
bit3-0: height of CRTC-B bit11-8
E8h CRTC-B / Sprite Starting Address Low
pointer to CRTC-B / sprite image in display memory.
(maximum size of sprites 64x64x4=1KB with 4 colors:
00b=color-0, 01b=color-255, 10b=transparent, 11b=reserved)
bit7-0: startaddress bit7-0
E9h CRTC-B / Sprite Starting Address Middle
bit7-0: startaddress bit15-8
EAh CRTC-B / Sprite Starting Address High
bit7-4: reserved
bit3-0: startaddress bit19-16
EBh CRTC-B / Sprite Row Offset Low
bit7-0: offset bit7-0
ECh CRTC-B / Sprite Row Offset High
bit7-4: revision ID (any ET4000/W32)
0000b=W32 0100b-1111b reserved
0001b=W32i
0010b=W32p
0011b=W32i, new
bit3-0: offset bit11-8
EDh CRTC-B Pixel Panning
bit7-3: reserved
bit2-0: CRTC-B pixel panning
EEh CRTC-B Color-Depth-Register / Hardware-Zoom
bit7-4: reserved (concerning databook ET4000/W32)
bit7-6: vertical zoom (undocumented)
(original ET4000/W32 ok, doesn't work properly
with some ET4000/W32i)
00b=zoomx1 10b=zoomx3
01b=zoomx2 11b=zoomx4
bit5-4: horizontal zoom (undocumented)
(original ET4000/W32 ok, doesn't work properly
with some ET4000/W32i)
00b=zoomx1 10b=zoomx3
01b=zoomx2 11b=zoomx4
bit3-0: bit/pixel
0000b=1 0011b=8
0001b=2 0100b=16
0010b=4
EFh CRTC-B / Sprite Control
bit7-2: reserved
bit1 : 1=2nd CRTC-B image overlays main CRTC-A image
0=CRTC-B image at pin SP1/0
bit0 : 1=enable CRTC-B
0=enable sprite (see F7h)
F7h Image Port Control
bit7 : 1=CRTC-B or sprite active
0=CRTC-B and sprite not active
bit6-0: reserved
----------P22E822EF--------------------------
PORT 22E8-22EF - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
22E8w -W CRT control: display control
----------P23902393--------------------------
PORT 2390-2393 - cluster (adapter 4)
--------V-P23C023CF--------------------------
PORT 23C0-23CF - Compaq QVision - BitBLT engine
--------X-P240024FF--------------------------
PORT 2400-24FF - available for EISA slot 2
----------P2465------------------------------
PORT 2465 - Compaq Contura Aero
SeeAlso: PORT 1C65h"Compaq",PORT 2065h"Compaq"
2465 R- current battery power level
(166 fully-charged, 130 = LowBat1)
----------P27C6------------------------------
PORT 27C6 - Compaq LTE Lite - LCD TIMEOUT
27C6 RW LCD timeout in minutes
--------X-P280028FF--------------------------
PORT 2800-28FF - available for EISA slot 2
--------V-P28E9------------------------------
PORT 28E9 - 8514/A - WD Escape Functions
--------V-P2C802C8F--------------------------
PORT 2C80-2C8F - VESA XGA Video in EISA slot 2
SeeAlso: PORT 1C80h-1C83h,PORT 1C88h-1C8Fh
--------X-P2C802C83--------------------------
PORT 2C80-2C83 - EISA board product ID (board in slot 2)
SeeAlso: PORT 1C80h-1C83h
--------X-P2C84------------------------------
PORT 2C84 - EISA CONFIGURATION FLAGS (board in slot 2)
2C84 RW configuration flags (see #P356)
--------X-P300030FF--------------------------
PORT 3000-30FF - available for EISA slot 3
--------S-P32203227--------------------------
PORT 3220-3227 - serial port 3, description same as 03F8
--------S-P3228322F--------------------------
PORT 3228-322F - serial port 4, description same as 03F8
--------V-P33C033CF--------------------------
PORT 33C0-33CF - Compaq QVision - BitBLT engine
--------X-P340034FF--------------------------
PORT 3400-34FF - available for EISA slot 3
--------d-P35103513--------------------------
PORT 3510-3513 - ESDI primary harddisk controller
Range: PORT 3510h-3513h (primary) or PORT 3518h-351Bh (secondary)
SeeAlso: PORT 3518h,PORT 01F0h-01F7h
3510w R- status word
3510w -W command word
3512 R- basic status
3512 -W basic control
3513 R- interrupt status
3513 -W attention
--------d-P3518351B--------------------------
PORT 3518-351B - ESDI secondary harddisk controller
Range: PORT 3510h-3513h (primary) or PORT 3518h-351Bh (secondary)
SeeAlso: PORT 3510h,PORT 01F0h-01F7h
3518w R- status word
3518w -W command word
351A R- basis status
351A -W basic control
351B R- interrupt status
351B -W attention
--------d-P3540354F--------------------------
PORT 3540-354F - IBM SCSI (Small Computer System Interface) adapter
--------d-P3550355F--------------------------
PORT 3550-355F - IBM SCSI (Small Computer System Interface) adapter
--------d-P3560356F--------------------------
PORT 3560-356F - IBM SCSI (Small Computer System Interface) adapter
--------d-P3570357F--------------------------
PORT 3570-357F - IBM SCSI (Small Computer System Interface) adapter
--------V-P36EE------------------------------
PORT 36EE - ATI Mach8/Mach32 - FIFO OPTION
SeeAlso: PORT 6AEEh,PORT 6EEEh,PORT 72EEh,PORT 76EEh,PORT 7AEEh,PORT 8EEEh
36EE -W FIFO option
bit 0: generate wait states if FIFO >= half full
(0=only when FIFO full)
bit 1: force 8-bit host data I/O
--------X-P380038FF--------------------------
PORT 3800-38FF - available for EISA slot 3
--------X-P3C003CFF--------------------------
PORT 3C00-3CFF - available for EISA slot 3
--------V-P3C803C8F--------------------------
PORT 3C80-3C8F - VESA XGA Video in EISA slot 3
3C80-3C83 RW EISA Video ID
3C84 RW EISA Video expansion board control
3C85 RW EISA Setup control
3C88 RW EISA Video Programmable Option Select 0
3C89-3C8F RW EISA Video Programmable Option Select 1-7
SeeAlso: PORT 1C80h-1C8Fh"XGA",PORT 2C80h-2C8Fh"XGA",PORT 7C80h-7C8Fh"XGA"
--------X-P3C803C83--------------------------
PORT 3C80-3C83 - EISA board product ID (board in slot 3)
SeeAlso: PORT 1C80h-1C83h
--------X-P3C84------------------------------
PORT 3C84 - EISA CONFIGURATION FLAGS (board in slot 3)
3C84 RW configuration flags (see #P356)
--------X-P400040FF--------------------------
PORT 4000-40FF - available for EISA slot 4
----------P42204227--------------------------
PORT 4220-4227 - serial port, description same as 03F8
----------P4228422F--------------------------
PORT 4228-422F - serial port, description same as 03F8
----------P42E042EF--------------------------
PORT 42E0-42EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
42E1 RW GPIB (adapter 2)
--------V-P42E8------------------------------
PORT 42E8 - 8514/A and hardware-compatible video cards
Note: supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
42E8w R- Misc. control: Subsystem Status
42E8w -W Misc. control: Subsystem Control (see #P358)
Bitfields for 8514/A Subsystem Control Register:
Bit(s) Description (Table P358)
15-14 GP_RESET
W 00 no change
01 normal operation
02 reset graphics processor and FIFO
11 W enable interrupt when processor idle
10 W enable interrupt on invalid I/O
9 W enable interrupt if inside scissors region
8 W enable vertical blanking interval interrupt
6-4 R monitor ID
3 acknowledge idle interrupt (and clear)
2 acknowledge invalid I/O interrupt (and clear)
1 acknowledge inside-scissors interrupt (and clear)
0 acknowledge vertical blanking interrupt (and clear)
--------V-P42EC------------------------------
PORT 42EC - ATI Mach64 - ???
SeeAlso: PORT 42EDh"Mach64"
42EC RW ???
bits 1-0: ???
--------V-P42ED------------------------------
PORT 42ED - ATI Mach64 - ???
SeeAlso: PORT 42ECh"Mach64",PORT 42EFh
42ED R? ???
--------V-P42EE42EF--------------------------
PORT 42EE-42EF - ATI Mach32 - MEMORY BOUNDARY REGISTER
SeeAlso: PORT 5EEEh"Mach32"
42EEw RW memory boundary
bits 3-0: VGA/8514 boundary in 256K units (VGA only below, 8514 above)
bit 4: partition enable: VGA and 8514 drawing engines may only write
within their respective partitions
bits 15-5: reserved
--------V-P42EF------------------------------
PORT 42EF - ATI Mach64 - ???
SeeAlso: PORT 42EDh"Mach64"
42EF R? ???
--------X-P440044FF--------------------------
PORT 4400-44FF - available for EISA slot 4
----------P4F15------------------------------
PORT 4F15 - Tseng Labs ET6000 - Read EDID through Display Data Channel
--------V-P46E8------------------------------
PORT 46E8 - VGA video adapter enable
Note: IBM uses this port for adapter-card VGAs only, and PORT 03C3h for
motherboard VGA only (see 03C3 for details)
SeeAlso: PORT 03C3h,PORT 46E8h"8514/A"
46E8 rW Misc. control: enable flags / select ROM page (8514/A) (see #P359)
Bitfields for VGA miscellaneous control register:
Bit(s) Description (Table P359)
7-5 unused or vendor-specific
4 setup for POS registers (MCA)
3 enable video I/O ports and video buffer
2-0 unused or vendor-specific
--------V-P46E8------------------------------
PORT 46E8 - 8514/A and compatible video cards (e.g. ATI Graphics Ultra)
Note: this register is readable on the C&T 82c480 chipset
SeeAlso: PORT 46E8h"VGA"
46E8w -W ROM page select (see #P360)
Bitfields for 8514/A ROM page select register:
Bit(s) Description (Table P360)
2-0 select which 4K page of 32K ROM to map at segment C700h
3 enable VGA
4 select VGA setup mode
15-5 reserved (0)
--------V-P46EE------------------------------
PORT 46EE - ATI Mach32 - ???
46EEw RW ???
--------V-P46EF------------------------------
PORT 46EF - ATI Mach64 - ???
Note: the Mach64 BIOS reads the value of this port and multiplies it by 100
SeeAlso: PORT 66ECh"Mach64"
--------X-P480048FF--------------------------
PORT 4800-48FF - available for EISA slot 4
--------V-P4AE84AEF--------------------------
PORT 4AE8-4AEF - 8514/A and compatible video cards - CRT CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
4AE8w -W CRT control: Advanced function control (see also #P361)
(02h = VGA mode, 03h = 480-line mode, 07h = 768-line mode)
Bitfields for S3 8514/A-compatible Advanced Function Control register:
Bit(s) Description (Table P361)
0 enable enhanced functions
1 reserved (1)
2 (911-928) screen size (1 = 800x600 or 1024x768, 0=640x480)
4 (928+) enable linear addressing (see also #P308)
5 (928+) enable memory-mapped I/O
6 (928 only) enable Write Posting
--------V-P4AEE------------------------------
PORT 4AEE - ATI Mach32 - ???
4AEEw RW ???
--------X-P4C004CFF--------------------------
PORT 4C00-4CFF - available for EISA slot 4
--------X-P4C804C83--------------------------
PORT 4C80-4C83 EISA board product ID (board in slot 4)
SeeAlso: PORT 1C80h-1C83h
--------V-P4C804C8F--------------------------
PORT 4C80-4C8F - VESA XGA Video in EISA slot 4 (see 3C80-3C8F)
SeeAlso: PORT 1C80h-1C8Fh,PORT 6C80h-6C8Fh
--------X-P4C84------------------------------
PORT 4C84 - EISA CONFIGURATION FLAGS (board in slot 4)
4C84 RW configuration flags (see #P356)
--------X-P500050FF--------------------------
PORT 5000-50FF - available for EISA slot 5
--------S-P52205227--------------------------
PORT 5220-5227 - serial port, description same as 03F8
--------S-P5228522F--------------------------
PORT 5228-522F - serial port, description same as 03F8
--------V-P52E852E9--------------------------
PORT 52E8-52E9 - C&T 82c480 - EXTENDED CONFIGURATION REGISTER 0
Note: the 82c480 is an 8514/A-compatible video chipset
SeeAlso: PORT 56E8h"C&T",PORT 5AE8h"C&T",PORT 5EE8h"C&T"
52E8w RW Extended Configuration Register 0
--------V-P52EE52EF--------------------------
PORT 52EE-52EF - ATI Mach32 - SCRATCH REGISTER 0 (USED FOR ROM LOCATION)
Note: ATI video BIOS sets this port according to the segment address of the
BIOS if >= C000h, as ((seg-C000h) shr 7)
SeeAlso: PORT 56EEh"Mach32"
52EEw RW scratch register 0: Video ROM address
--------X-P540054FF--------------------------
PORT 5400-54FF - available for EISA slot 5
--------V-P56E856E9--------------------------
PORT 56E8-56E9 - C&T 82c480 - EXTENDED CONFIGURATION REGISTER 1
Note: the 82c480 is an 8514/A-compatible video chipset
SeeAlso: PORT 52E8h"C&T",PORT 5AE8h"C&T",PORT 5EE8h"C&T"
56E8w RW Extended Configuration Register 1
--------V-P56EE56EF--------------------------
PORT 56EE-56EF - ATI Mach32 - SCRATCH REGISTER 1
SeeAlso: PORT 52EEh"Mach32"
56EEw RW scratchpad
--------X-P580058FF--------------------------
PORT 5800-58FF - available for EISA slot 5
--------V-P5AE85AE9--------------------------
PORT 5AE8-5AE9 - C&T 82c480 - EXTENDED CONFIGURATION REGISTER 2
Note: the 82c480 is an 8514/A-compatible video chipset
SeeAlso: PORT 52E8h"C&T",PORT 56E8h"C&T",PORT 5EE8h"C&T"
5AE8w RW Extended Configuration Register 2
--------V-P5AEE------------------------------
PORT 5AEE - ATI Mach32 - ???
5AEE RW ???
--------X-P5C005CFF--------------------------
PORT 5C00-5CFF - available for EISA slot 5
--------V-P5C805C8F--------------------------
PORT 5C80-5C8F - VESA XGA Video in EISA slot 5
SeeAlso: PORT 2C80h-2C8Fh,PORT 4C80h-4C8Fh,PORT 6C80h-6C8Fh
5C80d RW EISA Video ID
5C84 RW EISA Video expansion board control
5C85 RW EISA Setup control
5C88 RW EISA Video Programmable Option Select 0
5C89 RW EISA Video Programmable Option Select 1
5C8A RW EISA Video Programmable Option Select 2
5C8B RW EISA Video Programmable Option Select 3
5C8C RW EISA Video Programmable Option Select 4
5C8D RW EISA Video Programmable Option Select 5
5C8E RW EISA Video Programmable Option Select 6
5C8F RW EISA Video Programmable Option Select 7
--------X-P5C805C83--------------------------
PORT 5C80-5C83 EISA board product ID (board in slot 5)
SeeAlso: PORT 1C80h-1C83h
--------X-P5C84------------------------------
PORT 5C84 - EISA CONFIGURATION FLAGS (board in slot 5)
5C84 RW configuration flags (see #P356)
--------V-P5EE85EE9--------------------------
PORT 5EE8-5EE9 - C&T 82c480 - EXTENDED CONFIGURATION REGISTER 3
Note: the 82c480 is an 8514/A-compatible video chipset
SeeAlso: PORT 52E8h"C&T",PORT 56E8h"C&T",PORT 5AE8h"C&T"
5EE8w RW Extended Configuration Register 3
----------P5EEE------------------------------
PORT 5EEE - ATI Mach32 - MEMORY APERTURE CONFIGURATION REGISTER
SeeAlso: PORT 42EEh"Mach32"
5EEEw RW Memory Aperture Configuration (see #P362)
Bitfields for ATI Mach32 Memory Aperture Configuration Register:
Bit(s) Description (Table P362)
1-0 direct memory interface mapping
00 disabled
01 1M aperture (not on PCI)
10 4M aperture
11 reserved
3-2 1M page select (not on PCI)
00 page 0
01 page 1
10 page 2
11 page 3
11-8 (ISA) memory aperture location, 0-15 MB
13-8 (EISA) memory aperture location, 0-63 MB
14-8 (VLB) memory aperture location, 0-127 MB [*]
15-4 (PCI) memory aperture location, 0-4095 MB
13-8 (MCA 16-bit) memory aperture location, 0-63 MB
14-8 (MCA 32-bit) memory aperture location, 0-127 MB
Note: [*] if PORT 16EEh bit 3 is set and PORT FAEEh is non-zero, bits 15-4
are used to specify an address from 0-4095 MB
--------X-P600060FF--------------------------
PORT 6000-60FF - available for EISA slot 6
----------P62E062EF--------------------------
PORT 62E0-62EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
62E1 RW GPIB (adapter 3)
--------V-P63C063CF--------------------------
PORT 63C0-63CF - Compaq QVision - BitBLT engine
--------X-P640064FF--------------------------
PORT 6400-64FF - available for EISA slot 6
--------V-P66EC------------------------------
PORT 66EC - ATI Mach64 - ???
SeeAlso: PORT 6AECh"Mach64"
--------X-P680068FF--------------------------
PORT 6800-68FF - available for EISA slot 6
--------V-P6AEC6AED--------------------------
PORT 6AEC-6AED - ATI Mach64 - ???
SeeAlso: PORT 66ECh"Mach64"
--------V-P6AEE------------------------------
PORT 6AEE - ATI Mach8/Mach32 - MAXIMUM WAIT STATES
SeeAlso: PORT 36EEh,PORT 6EEEh,PORT 76EEh,PORT 7AEEh,PORT 8EEEh
6AEE RW maximum wait states (see #P363)
Bitfields for ATI Mach8/Mach32 wait state configuration:
Bit(s) Description (Table P363)
10 leave alone ("PASSTHROUGH_OVERRIDE")
9 enable for 16-bit I/O
8 0=horizontal degree-mode line draws
--------X-P6C006CFF--------------------------
PORT 6C00-6CFF - available for EISA slot 6
--------X-P6C806C83--------------------------
PORT 6C80-6C83 - EISA board product ID (board in slot 6)
SeeAlso: PORT 1C80h-1C83h
--------V-P6C806C8F--------------------------
PORT 6C80-6C8F - VESA XGA Video in EISA slot 1
SeeAlso: PORT 1C80h-1C8Fh"XGA",PORT 2C80h-2C8Fh"XGA",PORT 5C80h-5C8Fh"XGA"
6C80d RW EISA Video ID (see PORT 1C80h-1C83h)
6C84 RW EISA Video expansion board control
6C85 RW EISA Setup control
6C88 RW EISA Video Programmable Option Select 0
6C89 RW EISA Video Programmable Option Select 1
6C8A RW EISA Video Programmable Option Select 2
6C8B RW EISA Video Programmable Option Select 3
6C8C RW EISA Video Programmable Option Select 4
6C8D RW EISA Video Programmable Option Select 5
6C8E RW EISA Video Programmable Option Select 6
6C8F RW EISA Video Programmable Option Select 7
--------X-P6C84------------------------------
PORT 6C84 - EISA CONFIGURATION FLAGS (board in slot 6)
6C84 RW configuration flags (see #P356)
--------V-P6EEC------------------------------
PORT 6EEC - ATI Mach64 - ???
SeeAlso: PORT 6AECh"Mach64"
--------V-P6EEE------------------------------
PORT 6EEE - ATI Mach8/Mach32 - ENGINE VIDEO BUFFER OFFSET LOW
SeeAlso: PORT 72EEh
6AEEw -W low 16 bits of video buffer starting offset
--------X-P700070FF--------------------------
PORT 7000-70FF - available for EISA slot 7
--------V-P72EC------------------------------
PORT 72EC - ATI Mach64 - ???
SeeAlso: PORT 66ECh"Mach64",PORT 72EFh"Mach64"
--------V-P72EE------------------------------
PORT 72EE - ATI Mach8/Mach32 - ENGINE VIDEO BUFFER OFFSET HIGH
SeeAlso: PORT 6EEEh
72EE -W high bits of video buffer starting offset
bits 1-0 for Mach-8
bits 3-0 for Mach-32
--------V-P72EE------------------------------
PORT 72EE - ATI Mach8/Mach32 - BOUNDS ACCUMULATOR (LEFT)
SeeAlso: PORT 76EEh"BOUNDS",PORT 7AEEh"BOUNDS",PORT 7EEEh"BOUNDS"
72EEw R- left edge of bounding box for points written via Line Draw register
--------V-P72EF------------------------------
PORT 72EF - ATI Mach64 - ???
SeeAlso: PORT 66ECh"Mach64",PORT 72ECh"Mach64"
--------X-P740074FF--------------------------
PORT 7400-74FF - available for EISA slot 7
--------V-P76EE------------------------------
PORT 76EE - ATI Mach8/Mach32 - ENGINE DISPLAY PITCH
SeeAlso: PORT 6AEEh,PORT 7AEEh
76EE -W display pitch
--------V-P76EE------------------------------
PORT 76EE - ATI Mach8/Mach32 - BOUNDS ACCUMULATOR (TOP)
SeeAlso: PORT 72EEh"BOUNDS",PORT 7AEEh"BOUNDS",PORT 7EEEh"BOUNDS"
76EEw R- top edge of bounding box for points written via Line Draw register
--------X-P780078FF--------------------------
PORT 7800-78FF - available for EISA slot 7
--------V-P7AEE------------------------------
PORT 7AEE - ATI Mach8/Mach32 - EXTENDED GRAPHICS ENGINE CONGIFURATION
SeeAlso: PORT 8EEEh
7AEEw -W extended graphics engine configuration (see #P364)
Bitfields for Mach8/Mach32 extended graphics engine configuration:
Bit(s) Description (Table P364)
15 drawing pixel size to be written next (68800-6 only)
14 enable 8-bit DAC (Mach-32 only)
13-12 DAC address inputs RS(3:2) control (Mach-32 only)
11 display pixel size to be written next (68800-6 only)
10 24-bit color order (Mach-32 only)
0 = RGB
1 = BGR
9 24-bit color configuration: pixels use 4 bytes instead of three
8 DAC processes four pixels in parallel (Mach-32 only)
7-6 16-bits-per-color word format (Mach-32 only)
00 RGB(5,5,5)
01 RGB(5,6,5)
10 RGB(6,5,5)
11 RGB(6,6,4)
5-4 number of bits per pixel (Mach-32 only)
00 four
01 eight
10 sixteen
11 twenty-four
3 report monitor alias instead of actual monitor
2-0 alternate monitor ID (alias)
--------V-P7AEE------------------------------
PORT 7AEE - ATI Mach8/Mach32 - BOUNDS ACCUMULATOR (RIGHT)
SeeAlso: PORT 72EEh"BOUNDS",PORT 76EEh"BOUNDS",PORT 7EEEh"BOUNDS"
7AEEw R- right edge of bounding box for points written via Line Draw register
--------X-P7C007CFF--------------------------
PORT 7C00-7CFF - available for EISA slot 7
--------X-P7C807C83--------------------------
PORT 7C80-7C83 - EISA board product ID (board in slot 7)
SeeAlso: PORT 1C80h-1C83h
--------V-P7C807C8F--------------------------
PORT 7C80-7C8F - VESA XGA Video in EISA slot 7
SeeAlso: PORT 1C80h-1C8Fh,PORT 6C80h-6C8Fh
7C80-7C83 RW EISA Video ID
7C84 RW EISA Video expansion board control
7C85 RW EISA Setup control
7C88 RW EISA Video Programmable Option Select 0
7C89-7C8F RW EISA Video Programmable Option Select 1-7
--------X-P7C84------------------------------
PORT 7C84 - EISA CONFIGURATION FLAGS (board in slot 7)
7C84 RW configuration flags (see #P356)
--------V-P7EEE------------------------------
PORT 7EEE - ATI Mach8/Mach32 - BOUNDS ACCUMULATOR (RIGHT)
SeeAlso: PORT 72EEh"BOUNDS",PORT 76EEh"BOUNDS",PORT 7AEEh"BOUNDS"
7EEEw R- right edge of bounding box for points written via Line Draw register
--------X-P800080FF--------------------------
PORT 8000-80FF - available for EISA slot 8
----------P82E082EF--------------------------
PORT 82E0-82EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
82E1 RW GPIB (adapter 4)
--------V-P82E882EF--------------------------
PORT 82E8-82EF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT 86E8h
82E8w -W drawing control: current Y position
--------S-P82F882FF--------------------------
PORT 82F8-82FF - serial port, description same as 03F8
--------V-P83C083CF--------------------------
PORT 83C0-83CF - Compaq QVision - Line Draw Engine
--------V-P83C4------------------------------
PORT 83C4 - Compaq Qvision EISA - Virtual Controller Select
--------V-P83C683C9--------------------------
PORT 83C6-83C9 - Compaq Qvision EISA - DAC color registers
--------S-P83F883FF--------------------------
PORT 83F8-83FF - serial port, description same as 03F8
--------X-P840084FF--------------------------
PORT 8400-84FF - available for EISA slot 8
--------V-P86E886EF--------------------------
PORT 86E8-86EF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT 82E8h,PORT 8AE8h
86E8w -W drawing control: current X position
--------X-P880088FF--------------------------
PORT 8800-88FF - available for EISA slot 8
--------V-P8AE88AEF--------------------------
PORT 8AE8-8AEF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT 82E8h,PORT 86E8h
8AE8w -W drawing control: destination Y position / axial step constant
Note: this port may be read on S3 chipsets
--------X-P8C008CFF--------------------------
PORT 8C00-8CFF - available for EISA slot 8
--------X-P8C808C83--------------------------
PORT 8C80-8C83 - EISA board product ID (board in slot 8)
SeeAlso: PORT 1C80h-1C83h
--------X-P8C84------------------------------
PORT 8C84 - EISA CONFIGURATION FLAGS (board in slot 8)
8C84 RW configuration flags (see #P356)
--------V-P8EE88EEF--------------------------
PORT 8EE8-8EEF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT DAEEh"Mach32"
8EE8w -W drawing control: destination X position / axial step constant
--------V-P8EEE------------------------------
PORT 8EEE - ATI Mach32 - READ EXTENDED GRAPHICS CONFIGURATION
SeeAlso: PORT 72EEh
8EEE R- read extended graphics configuration (see #P364)
--------X-P900090FF--------------------------
PORT 9000-90FF - available for EISA slot 9
--------V-P92E892EF--------------------------
PORT 92E8-92EF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
92E8w -W drawing control: Bresenham error term
--------X-P940094FF--------------------------
PORT 9400-94FF - available for EISA slot 9
--------V-P96E896EF--------------------------
PORT 96E8-96EF - 8514/A and hardware-compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
96E8w R- enter WD Enhanced Mode
96E8w -W drawing control: major axis pixel count
--------X-P980098FF--------------------------
PORT 9800-98FF - available for EISA slot 9
--------V-P9AE89AE9--------------------------
PORT 9AE8-9AE9 - 8514/A Graphics Processor Status
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
9AE8w R- drawing control: graphic processor status (see #P365)
9AE8w -W drawing control: command register (see #P366)
Bitfields for 8514/A graphic processor status:
Bit(s) Description (Table P365)
15-10 reserved
9 hardware busy
8 data ready
7-0 status of queue (0=empty, 1=filled)
(each bit represents a position in queue)
SeeAlso: #P366
Bitfields for 8514/A command register :
Bit(s) Description (Table P366)
15-13 command
000 = no operation
001 = draw vector
010 = fast rectangle fill
011 = rectangle fill vertical #1
100 = rectangle fill vertical #2 (4 pixels)
101 = draw vector, 1 pixel/scanline
110 = copy rectangle
111 = reserved
12 byte sequence (0=high byte first, 1=low byte first)
11-10 reserved
9 enable 16-bit write access (16BIT)
8 0=use 8514/A data, 1=pixel data trans reg (PCDATA)
7 0=draw vector above, 1=draw vector below (INC_Y)
6 0=x is maj. axis, 1=y is maj. axis (YMAJAXIS)
5 0=draw vector left, 1=draw vector right (INC_X)
4 0=move only, 1=draw and move (DRAW)
3 0=Bresenham line, 1=direct vector (LINETYPE)
2 0=draw last pixel, 1=don't draw last pixel (LASTPIX)
1 0=single pixel, 1=4pixel (PLANAR)
0 0=read data, 1=write data (RD/WR)
SeeAlso: #P365
--------V-P9AEE------------------------------
PORT 9AEE - ATI Mach8/Mach32 - LINEDRAW INDEX REGISTER
SeeAlso: PORT FEEEh
9AEE -W linedraw index register (specifies interpretation of PORT FEEEh)
(see #P367)
(Table P367)
Values for ATI Mach8/Mach32 Linedraw Index Register:
00h set current X
01h set current Y
02h set Line End X
03h set Line End Y, draw line, and reset register to 02h
04h set current X (perform moves instead of draws)
05h set current Y and reset register to 04h
--------X-P9C009CFF--------------------------
PORT 9C00-9CFF - available for EISA slot 9
--------X-P9C809C83--------------------------
PORT 9C80-9C83 - EISA board product ID (board in slot 9)
SeeAlso: PORT 1C80h-1C83h
--------X-P9C84------------------------------
PORT 9C84 - EISA CONFIGURATION FLAGS (board in slot 9)
9C84 RW configuration flags (see #P356)
--------V-P9EE8------------------------------
PORT 9EE8 - 8514/A and compatible video cards - SHORT STROKE
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
9EE8w -W short line vector transfer
--------S-PA220------------------------------
PORT A220 - soundblaster support in AMI Hi-Flex BIOS ????
----------PA2E0A2EF--------------------------
PORT A2E0-A2EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
A2E1 RW GPIB (adapter 5)
--------V-PA2E8A2EF--------------------------
PORT A2E8-A2EF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT A6E8h
A2E8w -W drawing control: background color
--------V-PA2EEA2EF--------------------------
PORT A2EE-A2EF - ATI Mach8/Mach32 - LINE DRAW OPTIONS
SeeAlso: PORT 8EEEh,PORT CEEEh
A2EEw RW line drawing options (see #P368)
Bitfields for ATI Mach8/Mach32 line drawing options:
Bit(s) Description (Table P368)
10-9 clipping mode
00 disable clip exception
01 stroked plain lines
10 polygon boundary lines
11 patterned lines
8 reset all Bounds Accumulator registers
7-5 OCTANT: direction for BitBlts or lines
3 direction specification
0 = Bresenham/Octant
bit 7: increment Y
bit 6: Y is major axis instead of X
bit 5: increment X
1 = line-length and degrees
OCTANT field species N*45 degrees
2 do NOT draw last pixel of a line
1 polyline draw
--------V-PA6E8A6EF--------------------------
PORT A6E8-A6EF - 8514/A and compatible video cards - DRAWING CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT A2E8h
A6E8w -W drawing control: foreground color
--------V-PAAE8AAEF--------------------------
PORT AAE8-AAEF - 8514/A and compatible video cards - WRITE MASK
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT AEE8h
AAE8w -W drawing control: write mask
--------V-PAEE8AEEF--------------------------
PORT AEE8-AEEF - 8514/A and compatible video cards - READ MASK
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT AAE8h
AEE8w -W drawing control: read mask
--------V-PAFFF------------------------------
PORT AFFF - VIDEO REGISTER
AFFF RW plane 0-3 system latch (video register)
--------S-PB220B227--------------------------
PORT B220-B227 - serial port, description same as 03F8
--------S-PB228B22F--------------------------
PORT B228-B22F - serial port, description same as 03F8
--------V-PB2E8B2EF--------------------------
PORT B2E8-B2EF - 8514/A and compatible video cards - COLOR COMPARE
Notes: supported by ATI Graphics Ultra
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
B2E8w -W drawing control: color compare
--------V-PB2EE------------------------------
PORT B2EE - ATI Mach32 - ???
B2EEw RW ???
--------V-PB6E8B6EF--------------------------
PORT B6E8-B6EF - 8514/A and compatible video cards - BACKGROUND MIX
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT BAE8h
B6E8w -W drawing control: background mix
--------V-PB6EE------------------------------
PORT B6EE - ATI Mach32 - ???
B6EEw RW ???
--------V-PBAE8BAEF--------------------------
PORT BAE8-BAEF - 8514/A and compatible video cards - FOREGROUND MIX
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
SeeAlso: PORT B6E8h
BAE8w -W drawing control: foreground mix
--------V-PBAEE------------------------------
PORT BAEE - ATI Mach32 - ???
BAEEw RW ???
--------V-PBEE8BEEF--------------------------
PORT BEE8-BEEF - 8514/A and compatible video cards - MULTIFUNCTION CONTROL
Notes: supported by ATI Mach8 and Mach32 chipsets
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
BEE8w -W drawing control: multi-function control
(index in bits 15-12, data in bits 11-0) (see #P369)
BEE8w R- (S3) value of register specified by current value of multi-function
index 0Fh
(Table P369)
Values for index into 8514/A multi-function drawing control registers:
00h RW minor axis pixel count
01h RW top scissors
02h RW left scissors
03h RW bottom scissors
04h RW right scissors
05h -W memory control register
08h -W fixed pattern low
09h -W fixed pattern high
0Ah RW data manipulation control
---S3 chipsets---
0Dh RW (S3 864/964) miscellaneous 2
0Eh RW (S3 801+) miscellaneous
0Fh -W (S3 801/805/928) read register select (see #P370)
(Table P370)
Values for S3 multifunction read select register:
00h PORT BEE8h register 00h
01h PORT BEE8h register 01h
02h PORT BEE8h register 02h
03h PORT BEE8h register 03h
04h PORT BEE8h register 04h
05h PORT BEE8h register 0Ah
06h PORT BEE8h register 0Eh
07h PORT 9AE8h (bits 11-0 only)
---S3 864/964 only---
08h PORT 42E8h (bits 11-0 only)
09h PORT 46E8h
0Ah PORT BEE8h register 0Dh
SeeAlso: #P369
----------PC000C004--------------------------
PORT C000-C004 - Intel Pentium mboard ("Neptune" chipset)
SeeAlso: PORT C050h,PORT C200h-C204h,INT 15/AX=DA8Ch,#0798 at INT 1A/AX=B10Ah
--------X-PC000CFFF--------------------------
PORT C000-CFFF - PCI Configuration Mechanism 2 - CONFIGURATION SPACE
Note: to access the configuration space, write the target bus number to
PORT 0CFAh, then write to the Configuration Space Enable register
(PORT 03F8h), and finally read or write the appropriate I/O
port(s) in the range C000h to CFFFh (where Cxrrh accesses location
'rr' in physical device 'x's configuration data)
SeeAlso: PORT 0CF8h"Mechanism 2",PORT 0CFAh"Mechanism 2"
SeeAlso: #0798 at INT 1A/AX=B10Ah
--------X-PC008------------------------------
PORT C008 - Intel Pentium mboard ("Neptune" chipset) - CHIPSET REVISION
Desc: the host/PCI bridge revision ID register is visible on this port when
the PCI configuration space has been opened via ports 0CF8h and 0CFAh
SeeAlso: PORT 0CF8h,PORT 0CFAh,PORT C000h-C004h,PORT C050h,PORT C065h
--------X-PC050------------------------------
PORT C050 - Intel Pentium mboard ("Neptune" chipset)
SeeAlso: PORT C052h
C050 RW ???
bit 0: ???
bit 1: ???
bit 2: enable secondary (L2) cache
--------X-PC051------------------------------
PORT C051 - Intel "Mercury"/"Neptune" chipsets - DETURBO SPEED CONTROL
SeeAlso: PORT 0CF9h
C051 RW slowdown factor when in de-turbo mode
--------X-PC052------------------------------
PORT C052 - Intel Pentium mboard ("Neptune" chipset)
SeeAlso: PORT 0CF8h,PORT 0CFAh,PORT C050h,PORT C059h,PORT C065h
C052 RW bit 0: ???
bit 1: ???
bits 6,7: ???
--------X-PC054------------------------------
PORT C054 - Intel Pentium mboard ("Neptune" chipset)
SeeAlso: PORT 0CF8h,PORT 0CFAh
C054 RW bit 2: ??? (set immediately upon booting)
--------X-PC059C05F--------------------------
PORT C059-C05F - Intel chipsets - PROGRAMMABLE ATTRIBUTE MAP
SeeAlso: #0851
C059 RW Programmable Attribute Map Register 0 (see #0902)
C05A RW Programmable Attribute Map Register 1
C05B RW Programmable Attribute Map Register 2
C05C RW Programmable Attribute Map Register 3
C05D RW Programmable Attribute Map Register 4
C05E RW Programmable Attribute Map Register 5
C05F RW Programmable Attribute Map Register 6 (see #0902)
--------X-PC060C067--------------------------
PORT C060-C067 - Intel chipsets - DRAM ROW BOUNDARY REGISTERS
Desc: these registers (some chipsets implement only four or six, rather than
eight) indicate the cumulative amount of memory in DRAM rows 0-N;
the last implemented boundary register contains the total amount of
installed memory
SeeAlso: INT 15/AX=DA88h,#0851
C060 RW DRAM Row Boundary register 0
C061 RW DRAM Row Boundary register 1
C062 RW DRAM Row Boundary register 2
C063 RW DRAM Row Boundary register 3
C064 RW DRAM Row Boundary register 4
C065 RW DRAM Row Boundary register 5
C066 RW DRAM Row Boundary register 6
C067 RW DRAM Row Boundary register 7
--------d-PC100C1FF--------------------------
PORT C100-C1FF - Intel Pentium mboard - PCTech RZ1000 EIDE controller
Desc: the PCI configuration registers for the EIDE controller are visible
on these ports when the PCI configuration space has been opened via
ports 0CF8h and 0CFAh
SeeAlso: PORT 03F0h"RZ1000",PORT 0CF8h,#0798 at INT 1A/AX=B10Ah
----------PC200C204--------------------------
PORT C200-C204 - Intel Pentium mboard ("Neptune" chipset)
Desc: the PCI configuration registers for the motherboard chipset are visible
on these ports when the PCI configuration space has been opened via
ports 0CF8h and 0CFAh
SeeAlso: #0798 at INT 1A/AX=B10Ah
--------S-PC220C227--------------------------
PORT C220-C227 - serial port, description same as 03F8
--------S-PC228C22F--------------------------
PORT C228-C22F - serial port, description same as 03F8
----------PC244------------------------------
PORT C244 - Intel Pentium mboard ("Neptune" chipset)
----------PC2E0C2EF--------------------------
PORT C2E0-C2EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
C2E1 RW GPIB (adapter 6)
--------V-PC2EE------------------------------
PORT C2EE - ATI Mach32 - ???
C2EEw RW ???
--------V-PC6EE------------------------------
PORT C6EE - ATI Mach32 - SHORT-STROKE VECTOR
C6EEw -W short-stroke vector
--------V-PCAEE------------------------------
PORT CAEE - ATI Mach32 - ???
CAEEw RW ???
----------PCEEE------------------------------
PORT CEEE - ATI Mach8/Mach32 - DATAPATH CONFIGURATION
SeeAlso: PORT 8EEEh
CEEEw -W datapath configuration (see #P371)
Bitfields for ATI Mach8/Mach32 datapath configuration:
Bit(s) Description (Table P371)
15-13 foreground color source
000 background color reg
001 foreground color reg
010 pixel transfer reg
011 VRAM BitBlt source
101 color pattern shift register
12 least-significant byte first
9 data width is 16 bits instead of 8 bits
8-7 background color source
00 background color reg
01 foreground color reg
10 pixel transfer reg
11 VRAM BitBlt source
6-5 monochrome data source
00 always one
01 mono pattern register
10 pixel transfer register
11 VRAM BitBlt source
4 enable drawing
2 read color data instead of monochrome data
1 enable polygon fill BitBlt
0 write data to drawing trajectory instead of reading from trajectory
--------S-PD220D227--------------------------
PORT D220-D227 - serial port, description same as 03F8
SeeAlso: PORT 03F8h,PORT D228h
--------S-PD228D22F--------------------------
PORT D228-D22F - serial port, description same as 03F8
SeeAlso: PORT 03F8h,PORT D220h
--------V-PD2EE------------------------------
PORT D2EE - ATI Mach32 - ???
D2EEw RW ???
--------V-PDAEEDAEF--------------------------
PORT DAEE-DAEF - ATI Mach8/Mach32 - SCISSORS REGION (LEFT)
SeeAlso: PORT 8EE8h,PORT DEEEh"SCISSORS",PORT E2EEh"SCISSORS"
SeeAlso: PORT E6EEh"SCISSORS"
DAEEw -W left edge of "scissors" drawing area (bits 11-0)
--------V-PDEEEDEEF--------------------------
PORT DEEE-DEEF - ATI Mach8/Mach32 - SCISSORS REGION (TOP)
SeeAlso: PORT DAEEh"SCISSORS",PORT E2EEh"SCISSORS",PORT E6EEh"SCISSORS"
DEEEw -W top edge of "scissors" drawing area (bits 11-0)
----------PE2E0E2EF--------------------------
PORT E2E0-E2EF - GPIB (General Purpose Interface Bus, IEEE 488 interface)
E2E1 RW GPIB (adapter 7)
--------V-PE2E8E2EF--------------------------
PORT E2E8-E2EF - 8514/A and compatible video cards - PIXEL DATA TRANSFER
Notes: supported by ATI Graphics Ultra
supported by S3 chipsets when PORT 03D4h register 40h bit 0 is set
E2E8w -W drawing control: pixel data transfer
E2EAw rW drawing control: pixel data transfer (S3 801+) for 32-bit transfers
--------V-PE2EEE2EF--------------------------
PORT E2EE-E2EF - ATI Mach8/Mach32 - SCISSORS REGION (BOTTOM)
SeeAlso: PORT DAEEh"SCISSORS",PORT DEEEh"SCISSORS",PORT E6EEh"SCISSORS"
E2EEw -W bottom edge of "scissors" drawing area (bits 11-0)
--------V-PE6EEE6EF--------------------------
PORT E6EE-E6EF - ATI Mach8/Mach32 - SCISSORS REGION (RIGHT)
SeeAlso: PORT DAEEh"SCISSORS",PORT DEEEh"SCISSORS",PORT E2EEh"SCISSORS"
E6EEw -W right edge of "scissors" drawing area (bits 11-0)
--------V-PFAEE------------------------------
PORT FAEE - ATI Mach32 - CHIP IDENTIFICATION REGISTER
SeeAlso: PORT 56EEh"Mach32",PORT 5EEEh"Mach32"
--------V-PFEEEFEEF--------------------------
PORT FEEE-FEEF - ATI Mach8/Mach32 - DIRECT LINE DRAW REGISTER
SeeAlso: PORT 9AEEh
FEEEw -W direct line-draw register
--------d-Pxxxx------------------------------
PORT xxxx - Future Domain TMC-3260 PCI SCSI adapter
Range: anywhere on 8 byte boundary???
Note: Future Domain TMC-3260 PCI SCSI adapter is based upon Future Domain
TMC-36C70 SCSI controller which is a PCI version of the TMC-18C30
ISA SCSI controller
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
--------d-Pxxxx------------------------------
PORT xxxx - AMD Am53C974A PC-SCSI II SCSI adapter
Range: anywhere, on a 128-port boundary
SeeAlso: #0823
+000 R- current transfer count register (low)
+000 -W start transfer count register (low)
+004 R- current transfer count register (middle)
+004 -W start transfer count register (middle)
+008 RW SCSI FIFO register
+00C RW SCSI command register
+010 R- SCSI status register
+010 -W destination ID
+014 R- interrupt status
+014 -W SCSI timeout
+018 R- internal state
+018 -W synchronous transfer period
+01C R- current FIFO/internal state
+01C -W synchronous offset
+020 RW control register 1
+024 -W clock factor
+028 -W reserved
+02C RW control register 2
+030 RW control register 3
+034 RW control register 4
+038 R- current transfer count register (high) / ID code
+038 -W start current transfer count (high)
+03C reserved
+040 RW DMA command
+044d RW DMA starting transfer count (bits 23-0)
+048d RW DMA starting physical address
+04C R DMA working byte counter
+050d R DMA working address counter
+054 R DMA status register
+058d RW DMA starting memory descriptor list address
+05Cd R DMA working memory descriptor list counter
+070d Rw SCSI bus and control (bits 25-24 and 21-0)
Notes: the SCSI registers are mapped on DWORD boundaries, even though for most
only the least-significant byte is used
see "Am53C974A PCscsi(tm) II Technical Manual, Revision 1.0"
(file 19113A.PDF) for further details, as well as (file 19084A.PDF)
--------d-Pxxxx------------------------------
PORT xxxx - Adaptec AHA-2920 PCI SCSI adapter
Range: anywhere on 8 byte boundary???
Note: Adaptec AHA-2920 PCI SCSI adapter is based upon Future Domain TMC-36C70
SCSI controller which is a PCI version of Future Domain TMC-18C30 ISA
SCSI controller
SeeAlso: PORT 0140h-014Fh"Future Domain TMC-16x0"
--------d-Pxxxx------------------------------
PORT xxxx - Intel 82371 - Bus Master IDE Registers
+000 RW command register, primary channel (see #P372)
+002 Rw status register, primary channel (see #P373)
+004d RW IDE descriptor table pointer, primary channel (see #P374)
+008 RW command register, secondary channel (see #P372)
+00A Rw status register, secondary channel (see #P373)
+00Cd RW IDE descriptor table pointer, secondary channel (see #P374)
Bitfields for Intel 82371 Bus Master IDE command register:
Bit(s) Description (Table P372)
7-4 reserved
3 bus master read/write control
=0 read
=1 write
2-1 reserved
0 start/stop bus master
=1 start
=0 stop
SeeAlso: #P373,#P374
Bitfields for Intel 82371 Bus Master IDE status register:
Bit(s) Description (Table P373)
7 reserved (0)
6 drive 1 is DMA-capable
5 drive 0 is DMA_capable
4-3 reserved
2 IDE interrupt pending
write 1 to this bit to clear it
1 IDE DMA error
write 1 to this bit to clear it
0 bus master IDE active (read-only)
SeeAlso: #P372,#P374
Bitfields for Intel 82371 Bus Master IDE descriptor table pointer register:
Bit(s) Description (Table P374)
31-2 descriptor table base address bits 31-2
1-0 reserved
Note: the descriptor table must not cross a 4K boundary
SeeAlso: #P372,#P373
----------Pxxxx------------------------------
PORT xxxx - Intel 82371SB - USB Host I/O Registers
InstallCheck: see #0913 at INT 1A/AX=B10Ah
SeeAlso: #0913
+000w RW USB command register (see #P375)
+002w Rw USB status (see #P376)
+004w RW USB interrupt enable (see #P377)
+006w RW Frame Number (see #P378)
+008d RW Frame List Base Address
(bits 11-0 must be written as zeros)
+00C RW Start of Frame Modify (see #P379)
+010w RW port 1 status/control (see #P380)
+012w RW port 2 status/control (see #P380)
Bitfields for Intel 82371SB USB command register:
Bit(s) Description (Table P375)
15-8 reserved
7 maximum packet size (0=32 bytes, 1=64 bytes)
6 Host Controller has been configured (set by software)
5 software debug mode
4 force global resume
3 enter global suspend mode
2 global reset
1 host controller reset
0 run/stop schedule (0=stop, 1=run)
SeeAlso: #P376
Bitfields for Intel 82371SB USB status register:
Bit(s) Description (Table P376)
15-6 reserved
5 host controller halted
4 host controller process error
3 PCI bus error
2 resume received
1 USB error interrupt
0 USB interrupt
Note: to clear a bit in this register, write a 1 to it
SeeAlso: #P375
Bitfields for Intel 82371SB USB interrupt enable register:
Bit(s) Description (Table P377)
15-4 reserved
3 enable short packet interrupts
2 enable Interrupt On Complete
1 enable Resume
0 enable Timeout/CRC
SeeAlso: #P376,#P378
Bitfields for Intel 82371SB Frame Number register:
Bit(s) Description (Table P378)
15-11 reserved
10-0 Frame List Current Index/Frame Number
incremented at end of each time frame (~1ms)
Note: only WORD writes are allowed to this register
SeeAlso: #P375,#P377
Bitfields for Intel 82371SB Start of Frame Modify register:
Bit(s) Description (Table P379)
7 reserved
6-0 SOF timing value (default 64)
Note: SOF cycle time equals 11936+timing value
SeeAlso: #P375
Bitfields for Intel 82371SB Port 1/2 status/control register:
Bit(s) Description (Table P380)
15-13 reserved (0)
12 suspend port
11-10 reserved
9 port in Reset State
8 low-speed device is attached (read-only)
7 reserved (1)
6 resume detected (read-only)
5-4 line status (read-only)
bit 4: D+ signal line
bit 5: D- signal line
3 port enabled/disabled status has changed
write 1 to this bit to clear it
2 port is enabled
1 connect status has changed
write 1 to this bit to clear it
0 current connect status (read-only)
Note: only WORD writes are permitted to this register
SeeAlso: #P375
--------p-Pxxxx------------------------------
PORT xxxx - AMD-645 - Power Management Control/Status Registers
Range: anywhere on ???-byte boundary
SeeAlso: #0848,#0849
--------!---CREDITS--------------------------
Wim Osterholt <wim@djo.wtm.tudelft.nl> Original File
Chuck Proctor <71534.2302@CompuServe.COM>
Richard W. Watson <73042.1420@CompuServe.COM>
Matthias Paul <mpaul@ibh.rwth-aachen.de>
Serguei Shtyliov <serge.fido@coudert.msk.ru> Xirlink XL-22x
Serguei Shtyliov <serge.fido@coudert.msk.ru> TMC-16x0 SCSI
Serguei Shtyliov <serge.fido@coudert.msk.ru> AHA-154x SCSI
MPU-401 MIDI
Some of the information in this list was extracted from Frank van Gilluwe's
_The_Undocumented_PC_, a must-have book for anyone programming down to the
"bare metal" of a PC.
Some of the information in this list from the shareware version of Dave
Williams' DOSREF, v3.0.
8514/A hardware ports found in FractInt v18.0 source file FR8514A.ASM
Compaq QVision info from the _COMPAQ_QVision_Graphics_System_Technical_
_Reference_Guide_, second edition (October 1993). Compaq part number
073A/0693. Much more to come!
AMI keyboard controller PORT 0064h commands from the American Megatrends, Inc.
_Version_KF_and_KH_Keyboard_Controller_BIOS_Reference_, available on the
AMI BBS and american.megatrends.com as KFKHMAN.ZIP.
Various chipset infos from "Het BIOS Boekje" 2nd edition, by Alle Metzlar,
ISBN 90-72260-59-7 (1995).
ATA-3 info from "AT Attachment-3 Interface (ATA-3) Revision 1", dated
April 21, 1995.
Some additional EISA info from _EISA_System_Architecture_ (second edition),
by MindShare, Inc. (Addison-Wesley 1995, ISBN 0-201-40995-X).
AMI BIOS diagnostics codes (port 0080h) from file CHECKPTS on AMI BBS.
Some S3 and additional ATI Mach8/Mach32 info from Richard F. Ferraro's
_Programmer's_Guide_to_the_EGA,_VGA,_and_Super_VGA_Cards_, third edition.
PCnet-ISA info from _Am79C960_PCnet-ISA(tm)_Technical_Manual_, May 1992,
available from www.amd.com as 16850B.PDF; additional details from file
16907B.PDF.
PCnet-SCSI info from _Am79C974 PCnet(tm)-SCSI_Combination_Ethernet_and_SCSI_
_Controller_for_PCI_Systems_, available from www.amd.com as 18681B.PDF.
PCnet-FAST info from _Am79C971 PCnet(tm)-FAST_Single-Chip_Full-Duplex_10/100_
_Mbps_Ethernet_Controller_for_PCI_Local_Bus_, available from www.amd.com as
20550B.PDF.
S.M.A.R.T. information from _Self-Monitoring,_Analysis,_and_Reporting_
_Technology_(S.M.A.R.T.)_(SFF-8035i)_, Revision 2.0, April 1, 1996.
Available as 8035r2_0.PDF from fission.dt.wdc.com/pub/standards/SFF/.
A variety of ports from Frank van Giluwe's _The_Undocumented_PC_, second
edition.
AWARD Plug-and-Play POST codes from
http://www.asus.com.tw/Products/TECHREF/BIOS/pnp-post.html Added 24aug97.
AWARD non-Plug-and-Play POST codes from
http://www.asus.com.tw/Products/TECHREF/BIOS/npnp-post.html Added 24aug97.
OPTi 82C206 configuration register from
ftp://ftp.opti.com/pub/chipsets/archive/206/Db026_01.pdf.
Added by Ralf Brown, 05sep97.
OPTi 82C281/2 data from "OPTI Cache Sx/AT: 82C281 Data Book", Revision 1.1,
22aug91. Available as ftp://ftp.opti.com/pub/chipsets/archive/206/82c281.pdf.
Added by Ralf Brown, 05sep97.
OPTi 82C283 data from "82C283: 386SX System Controller", available as
ftp://ftp.opti.com/pub/chipsets/archive/283/Db012_10.pdf.
Added by Ralf Brown, 05sep97.
OPTi 82C291 data from "82C291: SXWB PC/AT Chipset", available as
ftp://ftp.opti.com/pub/chipsets/archive/291/Db011_10.pdf.
Added by Ralf Brown, 05sep97.
OPTi 82C295 data from "82C295: SLCWB PC/AT Chipset", available as
ftp://ftp.opti.com/pub/chipsets/archive/295/Db010_10.pdf.
OPTi 82C381/82C382 data from "HiD/386 AT Chipset", available as
ftp://ftp.opti.com/pub/chipsets/archive/381/82c381.pdf. (to be added)
OPTi 82C391/82C392 data from "OPTi-386WB PC/AT Chipset: 82C391/82C392 Data
Book", Version 1.1, 19dec90, available as
ftp://ftp.opti.com/pub/chipsets/archive/391/82c391.pdf. (to be added)
OPTi 82C463MV data from "Mixed Voltage Single Chip Notebook: 82C463MV Data
Book", Version 1.0b, 30sep93, available as
ftp://ftp.opti.com/pub/chipsets/archive/463/Db463mv.pdf. (to be added)
OPTi 82C491/82C392 data from "OPTi-486WB PC/AT Chipset", Version 1.1, 26apr91,
available as ftp://ftp.opti.com/pub/chipsets/archive/491/Db491_11.pdf.
(to be added)
OPTi 82C465MV/MVA/MVB data from "";
ftp://ftp.opti.com/pub/chipsets/system/465/db016_20.pdf. (to be added)
OPTi 82C493/82C392 data from "OPTi-486SXWB PC/AT Chipset", Version 1.1,
16aug91; ftp://ftp.opti.com/pub/chipsets/archive/493/82c493_392.pdf.
(to be added)
OPTi "Vendetta" (82C750) data from "Vendetta Single-Chip MultiMedia PC
Solution: Preliminary Data Book"; available as
ftp://ftp.opti.com/pub/chipsets/system/vendetta/pd020_20.pdf. (to be added)
OPTi "FireLink" (82C861) data from "FireLink / FireBlast 82C861/82C871
PCI-to-USB Bus Bridges: Preliminary Data Book"; available as
ftp://ftp.opti.com/pub/chipsets/system/861/pd022_20.pdf. (to be added)
OPTi "FireFox" (82C824) data from "FireFox 82C824 32-bit PC Card Controller:
Preliminary Data Book", Revision 3.0, 26aug96; available as
ftp://ftp.opti.com/pub/chipsets/system/824/pd013_30.pdf. (to be added)
OPTi "FireBridge 2" (82C825) data from "FireBridge II 82C825 Docking Station
Controller Data Book", Revision 1.0, 27jun97; available as
ftp://ftp.opti.com/pub/chipsets/system/825/db046_10.pdf. (to be added)
OPTi "FireFly" (82C852) data from "FireFly 82C852 16-bit PC Card Controller:
Preliminary Data Book", Revision 1.0, 6jun96; available as
ftp://ftp.opti.com/pub/chipsets/system/852/pd018_10.pdf. (to be added)
OPTi "Viper" (82C556/557/558) chipset data from "Viper-DP Desktop Chipset for
the 3.3V Pentium Processor, M1 and K5 Processors: Data Book", Revision 1.0,
1/95; ftp://ftp.opti.com/pub/chipsets/archive/viper/Db023_10.pdf. (to be added)
--------!---Admin----------------------------
Highest Table Number = P384
--------!---FILELIST-------------------------
Please redistribute all of the files comprising the interrupt list (listed at
the beginning of the list and in INTERRUP.1ST) unmodified as a group, in a
quartet of archives named INTER56A through INTER56D (preferably the original
authenticated PKZIP archives), and the utility and hypertext programs in a trio
of additional archives called INTER56E.ZIP to INTER56G.ZIP.
Copyright (c) 1989,1990,1991,1992,1993,1994,1995,1996,1997 Ralf Brown
--------!---CONTACT_INFO---------------------
Internet: ralf@pobox.com (currently forwards to ralf@telerama.lm.com)
UUCP: {uunet,harvard}!pobox.com!ralf
FIDO: Ralf Brown 1:129/26.1
or post a message to me in the DR_DEBUG echo (I probably won't see it
unless you address it to me)
CIS: >INTERNET:ralf@pobox.com
