The MikeOS KB I/O project assembly routines...

Bazza — Thu Apr 22, 2010 7:34 pm

Author: Bazza

Posted: Thu Apr 22, 2010 7:34 pm

Hi all...

As promised the assembler code to use a modified KB as I/O
inside MikeOS and running from a netbook... :-O
Notice I have kept these as separate subroutines rather than
a single piece of code which would of course be smaller in
compiled size...

Code:

; CAPSLOCK ON/OFF sub-routines for MikeOS.
; Original copyright, (C)2010, B.Walker, G0LCU.
; For use with MikeBASIC and issued as Public Domain.

; CAPSLOCK.ASM, Version 0.00.10, assembly code.

; Assembled under MS-DOS using the AD86 combination.
; The binary is 48 bytes in size.

;CAPSON:
pushf       ;Store flags and all of the used
push ax    ;registers.
push dx    ;
push ds    ;
mov dx,0040h ;Point to the SEGMENT to access
mov ds,dx    ;the REAL time BYTE KB storage.
mov al,[0017h] ;Move the BYTE value from memory
         ;into the AL register.
or al,040h    ;SET the required bit, (bit 6),
         ;to a ~1~.
         ;NOTE, change this value for NUMLOCK!
mov [0017h],al ;Replace the modified byte back
         ;into the memory location.
int 9    ;Now execute the necessary interrupt.
pop ds    ;Restore the registers back to
pop dx    ;their original values...
pop ax    ;
popf       ;And the flags too.
ret       ;Return to the calling routine.

;CAPSOFF:
pushf       ;Store flags and all of the used
push ax    ;registers.
push dx    ;
push ds    ;
mov dx,0040h ;Point to the SEGMENT to access
mov ds,dx    ;the REAL time BYTE KB storage.
mov al,[0017h] ;Move the BYTE value from memory
         ;into the AL register.
and al,0bfh    ;RESET the required bit, (bit 6),
         ;to a ~0~, keeping all other bits intact.
         ;NOTE, change this value for NUMLOCK!
mov [0017h],al ;Replace the modified byte back
         ;into the memory location.
int 9    ;Now execute the necessary interrupt.
pop ds    ;Restore the registers back to
pop dx    ;their original values...
pop ax    ;
popf       ;And the flags too.
ret       ;Return to the calling routine.

; CAPSLOCK.ASM assembly code end.

; KBFALGS.ASM, Version 0.00.10.

; Keyboard flags memory location in "real time" READ only mode.
; Issued as PD for MikeOS and LXF.
; To work in conjuction with MikeBASIC.

; Keyoard HW modification, (C)2010, B.Walker, G0LCU.
; 8088 CPU instruction set compatible.
; Assembled under MS-DOS using AD86 combination,

;KBFLAGS:
pushf       ;Push all used registers
push ax    ;and flags.
push dx    ;
push ds    ;
mov dx,0040h ;Point to the SEGMENT 0x0040h.
mov ds,dx    ;Do it.
mov al,[0017h] ;Read the memory offset 0x0017h
         ;and place into the al register.
pop ds    ;Pop these two registers back.
pop dx    ;
mov [store],al ;Move the value in the registsr
         ;~AL~ into a known MikeOS memory
         ;location.
pop ax    ;Now pop the ~AX~ register back
popf       ;and the flags.
ret       ;Return back to calling routine.
store db 0c3h    ;The keyboard flags stored for
         ;my usage...
; END of flags read routine.

I have not given an explanation here as this will be part of
the project for MikeOS, but I suspect that there is enough
info inside the code...

For more information Google "segment:offset 0040:0017"...

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The MikeOS KB I/O project assembly routines...