HP Vectra Technical Reference Manual page 294

9.6 Time And Date Driver (lNT 1AH)
Table 9.2 describes functions provided
by
the BIOS to manage the CMOS clock and the software
clock.
Table 9.2
Time and Date Driver Function Code Summary
INT Function
Hex Equate
1AH INT_CLOCK
F1~RD_CLK_CNT
F1~SET __ CL~CNT
F1~GET_RTC
F1~SET_RTC
F1~GET_DATE
F1~SET_DATE
F1~SET--ALARM
F1 A-RESET--ALARM
Function
Value Definition
Time and date
OOH
Read current clock count
01 H
Set current clock count
02H
Read real-time clock
03 H
Set real-time clock
04H
Read date from real-time clock
05 H
Set date in real-time clock
06H
Set alarm
07H
Reset alarm
Time and Date Driver Function Definitions
F1A-RD_CLLCNT (AH = OOH)
Reads the current setting of the software clock. There are 18.2 counts per second.
On Exit: AL
=
Zero if the timer has not overflowed (not passed 24 hours since the last read).
Nonzero if time has overflowed.
CX
=
High word of the count. (There are 18.2 counts per second).
DX
=
Low word of count.
Registers Altered: AX, CX, DX
System Diivers 285