INT 1A,9 - Read RTC Alarm Time and Status (convertible,PS/2)
AH = 09 on return: CH = hours in BCD CL = minutes in BCD DH = seconds in BCD DL = alarm status: = 00 if alarm not enabled (AIE=0) = 01 if alarm enabled but will not power up system (AIE=1) = 02 if alarm will power up system (AIE=1) - see RTC