FreeDOS/kernel/initclk.c

75 lines
3.3 KiB
C

/****************************************************************/
/* */
/* initclk.c */
/* */
/* System Clock Driver - initialization */
/* */
/* 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. */
/****************************************************************/
#include "portab.h"
#include "init-mod.h"
#ifdef VERSION_STRINGS
static char *RcsId =
"$Id: initclk.c 1359 2008-03-09 16:11:10Z mceric $";
#endif
/* */
/* WARNING - THIS DRIVER IS NON-PORTABLE!!!! */
/* */
STATIC int InitBcdToByte(int x)
{
return ((x >> 4) & 0xf) * 10 + (x & 0xf);
}
void Init_clk_driver(void)
{
static iregs regsT = {0x200}; /* ah=0x02 */
static iregs regsD = {0x400, 0, 0x1400, 0x101};
/* ah=4, ch=20^ ^cl=0, ^dh=dl=1 (2000/1/1)
* (above date will be set on error) */
iregs dosregs;
init_call_intr(0x1a, &regsT); /* get BIOS time */
init_call_intr(0x1a, &regsD); /* get BIOS date */
/* DosSetDate */
dosregs.a.b.h = 0x2b;
dosregs.c.x = 100 * InitBcdToByte(regsD.c.b.h) /* century */
+ InitBcdToByte(regsD.c.b.l);/* year */
/* A BIOS with y2k (year 2000) bug will always report year 19nn */
if ((dosregs.c.x >= 1900) && (dosregs.c.x < 1980)) dosregs.c.x += 100;
dosregs.d.b.h = InitBcdToByte(regsD.d.b.h); /* month */
dosregs.d.b.l = InitBcdToByte(regsD.d.b.l); /* day */
init_call_intr(0x21, &dosregs);
/* DosSetTime */
dosregs.a.b.h = 0x2d;
dosregs.c.b.l = InitBcdToByte(regsT.c.b.l); /* minutes */
dosregs.c.b.h = InitBcdToByte(regsT.c.b.h); /* hours */
dosregs.d.b.h = InitBcdToByte(regsT.d.b.h); /*seconds */
dosregs.d.b.l = 0;
init_call_intr(0x21, &dosregs);
}