Function 22 - set system date/time.
Parameters:
- eax = 22 - function number
- ebx = 0 - set time
- ecx = 0x00SSMMHH - time in the binary-decimal code (BCD):
- HH=hour 00..23
- MM=minute 00..59
- SS=second 00..59
- ebx = 1 - set date
- ecx = 0x00DDMMYY - date in the binary-decimal code (BCD):
- DD=day 01..31
- MM=month 01..12
- YY=year 00..99
- ebx = 2 - set day of week
- ecx = 1 for Sunday, ..., 7 for Saturday
- ebx = 3 - set alarm clock
Returned value:
- eax = 0 - success
- eax = 1 - incorrect parameter
- eax = 2 - CMOS-battery was unloaded
Remarks:
- Value of installation of day of week seems to be doubtful,
as it a little where is used
(day of week can be calculated by date).
- Alarm clock can be set on operation in the given time every day.
But there is no existing system function to disable it.
- Operation of alarm clock consists in generation IRQ8.
- Generally CMOS supports for alarm clock set of value 0xFF
as one of parameters and it means that the appropriate parameter
is ignored. But current implementation does not allow this
(will return 1).
- Alarm clock is a global system resource; the set of
an alarm clock cancels automatically the previous set.
However, at moment no program uses it.