HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

            INT 1A,6 - Set Real Time Clock Alarm  (XT 286,AT,PS/2)

       AH = 06
       CH = hours in BCD
       CL = minutes in BCD
       DH = seconds in BCD

       on return:
       CF = 1 if alarm already set or clock inoperable

       - alarm setting is not relative like some sources claim, but the
         actually clock time the interrupt should occur
       - settings values must be in BCD
       - when the alarm time is reached INT 4A is executed
       - INT 4A vector should be replaced with address of the alarm
         handling interrupt routine before setting the alarm
       - INT 1A,7 should be called to disable the RTC alarm

Esc or Alt-X to exit int 1a,6 Home/PgUp/PgDn/End ←↑↓→
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