blob: 7c7bfbe2956b202c4fc9818e20892079095d1ed9 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
#include <kernel/io/io.h>
#include <kernel/lib/stdio.h>
unsigned char second;
unsigned char minute;
unsigned char hour;
unsigned char day;
unsigned char month;
unsigned int year;
int get_update_in_progress_flag()
{
outb(0x70, 0x0A);
return (inb(0x71) & 0x80);
}
unsigned char get_rtc_register(int reg)
{
outb(0x70, (uint8_t)reg);
return inb(0x71);
}
void read_rtc()
{
unsigned int century = 20; // ...
unsigned char last_second;
unsigned char last_minute;
unsigned char last_hour;
unsigned char last_day;
unsigned char last_month;
unsigned char last_year;
unsigned char last_century;
unsigned char registerB;
while (get_update_in_progress_flag())
;
second = get_rtc_register(0x00);
minute = get_rtc_register(0x02);
hour = get_rtc_register(0x04);
day = get_rtc_register(0x07);
month = get_rtc_register(0x08);
year = get_rtc_register(0x09);
// century = get_rtc_register(fadt->century); // TODO: Fix fadt table (page fault!)
// Try until the values are the same (fix for RTC updates)
do {
last_second = second;
last_minute = minute;
last_hour = hour;
last_day = day;
last_month = month;
last_year = (unsigned char)year;
last_century = (unsigned char)century;
while (get_update_in_progress_flag())
;
second = get_rtc_register(0x00);
minute = get_rtc_register(0x02);
hour = get_rtc_register(0x04);
day = get_rtc_register(0x07);
month = get_rtc_register(0x08);
year = get_rtc_register(0x09);
// century = get_rtc_register(fadt->century);
} while ((last_second != second) || (last_minute != minute) || (last_hour != hour) ||
(last_day != day) || (last_month != month) || (last_year != year) ||
(last_century != century));
registerB = get_rtc_register(0x0B);
if (!(registerB & 0x04)) {
second = (unsigned char)((second & 0x0F) + ((second / 16) * 10));
minute = (unsigned char)((minute & 0x0F) + ((minute / 16) * 10));
hour = (unsigned char)(((hour & 0x0F) + (((hour & 0x70) / 16) * 10)) |
(hour & 0x80));
day = (unsigned char)((day & 0x0F) + ((day / 16) * 10));
month = (unsigned char)((month & 0x0F) + ((month / 16) * 10));
year = (year & 0x0F) + ((year / 16) * 10);
// century = (century & 0x0F) + ((century / 16) * 10);
}
year += century * 100;
// Convert to 24h if necessary
if (!(registerB & 0x02) && (hour & 0x80)) {
hour = (unsigned char)(((hour & 0x7F) + 12) % 24);
}
}
void write_time()
{
read_rtc();
printf("Current time: %d:%d:%d %d/%d/%d\n", hour, minute, second, month, day, year);
}
|
