COMMENT $
Copyright (C) Magna Carta Software, Inc. 1987-1990.  All Rights Reserved.
BIOS_KBD -- Assembly language interface to BIOS keyboard INT 16H
Note: Emulates all of the features of bioskey() in the Turbo C and
_bios_keybrd() in MSC 5.0+ compiler libraries but additionally adds support
for Enhanced Keyboard functions.
File invocation syntax:
POWER C: MASM bkey /DM_I86xM=1
else:    MASM bkey /DM_I86xM=1 /DMSC
Where 'x' is one of: S C M L
Compatibility: MSC 5.0+/QC, POWER C v2.0+, TURBO C, WATCOM C
First version 11-08-87. Last update 06-07-91.
$

.LALL
.LIST
INCLUDE cmacros.mac

DEFSEG      BKEY _DATA


CSEG SEGMENT

;BIOS_KBD -- BIOS keyboard service.
;Returns:   EOF -- no key ready
;           scan code in high byte, char code in low byte
;Calls INT 16H, (including enhanced keyboard services).
;Nukes: AX, BX
;
START_PROC  bios_kbd    <_SHORT func>
        pushf
        mov     ah, func
        int     016h
        pushf
        cmp     BYTE PTR func, 1    ;is it service 1 (key ready)?
        je      testzflag
        cmp     BYTE PTR func, 11h  ;is it service 11 (enhanced service 1)
        je      testzflag
        popf
        jmp     SHORT is1
testzflag:
        popf
        jnz     is1                 ;ZF=1 => no char ready
        mov     ax,0FFFFh
is1:
        popf
END_PROC    bios_kbd

IFDEF DEBUG
main        PROC
            call    bios_kbd
            ret
main        ENDP
ENDIF

CSEG        ENDS
            END