ReactOS 0.4.15-dev-8422-g6219a1a
pcrtc.c
Go to the documentation of this file.
1/*
2 * FreeLoader
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19#include <freeldr.h>
20
21#define BCD_INT(bcd) (((bcd & 0xf0) >> 4) * 10 + (bcd &0x0f))
22
25{
26 static TIMEINFO TimeInfo;
27 REGS Regs;
28
29 for (;;)
30 {
31 /* Some BIOSes, such as the 1998/07/25 system ROM
32 * in the Compaq Deskpro EP/SB, leave CF unchanged
33 * if successful, so CF should be cleared before
34 * calling this function. */
35 Regs.x.eflags = 0;
36// __writeeflags(__readeflags() & ~EFLAGS_CF);
37
38 /* Int 1Ah AH=04h
39 * TIME - GET REAL-TIME CLOCK DATE (AT,XT286,PS)
40 *
41 * AH = 04h
42 * CF clear to avoid bug
43 * Return:
44 * CF clear if successful
45 * CH = century (BCD)
46 * CL = year (BCD)
47 * DH = month (BCD)
48 * DL = day (BCD)
49 * CF set on error
50 */
51 Regs.b.ah = 0x04;
52 Int386(0x1A, &Regs, &Regs);
53
54 if (!INT386_SUCCESS(Regs)) continue;
55
56 TimeInfo.Year = 100 * BCD_INT(Regs.b.ch) + BCD_INT(Regs.b.cl);
57 TimeInfo.Month = BCD_INT(Regs.b.dh);
58 TimeInfo.Day = BCD_INT(Regs.b.dl);
59
60 /* Some BIOSes leave CF unchanged if successful,
61 * so CF should be cleared before calling this function. */
62 Regs.x.eflags = 0;
63// __writeeflags(__readeflags() & ~EFLAGS_CF);
64
65 /* Int 1Ah AH=02h
66 * TIME - GET REAL-TIME CLOCK TIME (AT,XT286,PS)
67 *
68 * AH = 02h
69 * CF clear to avoid bug
70 * Return:
71 * CF clear if successful
72 * CH = hour (BCD)
73 * CL = minutes (BCD)
74 * DH = seconds (BCD)
75 * DL = daylight savings flag (00h standard time, 01h daylight time)
76 * CF set on error (i.e. clock not running or in middle of update)
77 */
78 Regs.b.ah = 0x02;
79 Int386(0x1A, &Regs, &Regs);
80
81 if (!INT386_SUCCESS(Regs)) continue;
82
83 TimeInfo.Hour = BCD_INT(Regs.b.ch);
84 TimeInfo.Minute = BCD_INT(Regs.b.cl);
85 TimeInfo.Second = BCD_INT(Regs.b.dh);
86
87 break;
88 }
89 return &TimeInfo;
90}
91
92/* EOF */
#define INT386_SUCCESS(regs)
Definition: pcbios.h:179
int __cdecl Int386(int ivec, REGS *in, REGS *out)
#define BCD_INT(bcd)
Definition: pcrtc.c:21
TIMEINFO * PcGetTime(VOID)
Definition: pcrtc.c:24
unsigned char ch
Definition: pcbios.h:138
unsigned char dl
Definition: pcbios.h:140
unsigned char cl
Definition: pcbios.h:137
unsigned char ah
Definition: pcbios.h:132
unsigned char dh
Definition: pcbios.h:141
unsigned long eflags
Definition: pcbios.h:105
Definition: fw.h:10
USHORT Month
Definition: fw.h:12
USHORT Day
Definition: fw.h:13
USHORT Minute
Definition: fw.h:15
USHORT Hour
Definition: fw.h:14
USHORT Second
Definition: fw.h:16
USHORT Year
Definition: fw.h:11
Definition: pcbios.h:159
DWORDREGS x
Definition: pcbios.h:160
BYTEREGS b
Definition: pcbios.h:163