Revised : 28/9/91@20:13EST
Western Digital WD1007A-WAH/WA2 disk controller
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WD1007A-WAH supports 2 ESDI disks, the WD1007A-WA2 supports 2 floppy drives
(high/low density, 3-1/2 or 5-1/4) as well.

BIOS Address Ranges
                         W1       W2      W3
 C8000 - 09FFF          2-3      2-3      jumper  **Factory setting
 CA000 - CBFFF          2-3      1-2      jumper
 CC000 - CDFFF          1-2      2-3      jumper 
 CE000 - CFFFF          1-2      1-2      jumper

Floppy Address Ranges
            W6
 37X       1-2
 3FX       2-3  **Factory setting

Primary/Secondary Hard Disk Address
           W12
 1FX       no jumper  **Factory setting
 17X       jumper

Mode Control
 W8  no jumper - forces a 10MHz drive to 35 sectors per track (supports 1:1
                 interleave)
     jumper    - controller reads Unformatted Bytes per Sector from the
                 drive

W14  no jumper - enables translation of # of sectors per track or
                 cylinders, for use with systems which can't handle more
                 than 17SPT or 1024 cylinders
     jumper    - disable physical to logical translation by the firmware

W15  no jumper - 4 bytes ECC (**Factory setting)
     jumper    - 7 bytes ECC 
 
Floppy Drive and Data Rate Selection Control

 W5  no jumper - single speed drive (125 nanoseconds precompensaton)
     jumper    - dual speed drive

 W7  1-2 jumpered - support floppy drive (WA2 only)

 Floppy Controller      W4          W13 (in etch)
    enable              no jumper   uncut
    disable             jumper      cut

Using the WD1007A BIOS to do a low level format of the drive

 Enter the BIOS routine through the DOS debug utility.  At the DEBUG prompt
type:
 G=C800:5 <CR>
This will execute a program stored at location 5 in ROM and produce a menu
for doing the low level setup of the drive.

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