FreeDOS/drivers/rdatclk.asm
2001-11-04 19:47:39 +00:00

117 lines
3.1 KiB
NASM

;
; File:
; rdatclk.asm
; Description:
; read the AT style clock from bios
;
; Copyright (c) 1995
; Pasquale J. Villani
; All Rights Reserved
;
; This file is part of DOS-C.
;
; DOS-C is free software; you can redistribute it and/or
; modify it under the terms of the GNU General Public License
; as published by the Free Software Foundation; either version
; 2, or (at your option) any later version.
;
; DOS-C is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
; the GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public
; License along with DOS-C; see the file COPYING. If not,
; write to the Free Software Foundation, 675 Mass Ave,
; Cambridge, MA 02139, USA.
;
; @Logfile: C:/dos-c/src/drivers/rdatclk.asv @
;
; @Header: /home/cvsroot/fdkernel/DRIVERS/RDATCLK.ASM,v 1.3 1999/04/12 03:19:44 jprice Exp @
;
; @Log: rdatclk.asm,v @
; Revision 1.1.1.1 2000/05/06 19:34:53 jhall1
; The FreeDOS Kernel. A DOS kernel that aims to be 100% compatible with
; MS-DOS. Distributed under the GNU GPL.
;
; Revision 1.3 1999/04/12 03:19:44 jprice
; more ror4 patches
;
; Revision 1.2 1999/03/29 17:08:31 jprice
; ror4 changes
;
; Revision 1.1.1.1 1999/03/29 15:40:31 jprice
; New version without IPL.SYS
;
; Revision 1.2 1999/01/22 04:16:39 jprice
; Formating
;
; Revision 1.1.1.1 1999/01/20 05:51:00 jprice
; Imported sources
;
;
; Rev 1.2 29 Aug 1996 13:07:10 patv
;Bug fixes for v0.91b
;
; Rev 1.1 01 Sep 1995 18:50:40 patv
;Initial GPL release.
;
; Rev 1.0 02 Jul 1995 8:00:16 patv
;Initial revision.
;
%include "..\kernel\segs.inc"
segment HMA_TEXT
;
;COUNT ReadATClock(bcdDays, bcdHours, bcdMinutes, bcdSeconds)
;BYTE *bcdDays;
;BYTE *bcdHours;
;BYTE *bcdMinutes;
;BYTE *bcdSeconds;
;
global _ReadATClock
_ReadATClock:
push bp
mov bp, sp
xor cx, cx ; cx=dx=0 check if present
xor dx, dx ; if it returns non-zero
clc ; necessary according to RBIL
mov ah,4
int 1ah
jc @RdATerror
or cx, cx
jnz @RdAT1140
or dx, dx
jnz @RdAT1140
@RdATerror: mov ax, 1
pop bp
ret
@RdAT1140:
clc
mov ah, 2
int 1ah
jc @RdATerror
; bcdSeconds = 10
; bcdMinutes = 8
; bcdHours = 6
; bcdDays = 4
mov bx,word [bp+6] ;bcdHours
mov byte [bx],ch ;Hours
mov bx,word [bp+8] ;bcdMinutes
mov byte [bx],cl ;Minutes
mov bx,word [bp+10] ;bcdSeconds
mov byte [bx],dh ;Seconds
clc
mov ah,4
int 1ah
jc @RdATerror
mov bx,word [bp+4] ;bcdDays
mov word [bx],dx ;Days
mov word [bx+2],cx
sub ax,ax
pop bp
ret