Int 1Ah Functions

AH = 00h: Read BIOS Time

AH = 01h: Set BIOS Time

AH = 02h: Read RTC Time

AH = 03h: Set RTC Time

AH = 04h: Read RTC Date

AH = 05h: Set RTC Date

AH = 06h: Set Alarm

AH = 07h: Reset Alarm

AH = 08h: Set Power-On Alarm

AH = 09h: Get the Current Alarm Setting

AH = 0Ah: Read Day Counter

AH = 0Bh: Write Day Counter

AH = 0Ch: Set Future Alarm

AH = 0Dh: Set Future Power-On Alarm

AH = 0Eh: Get the Current Alarm Setting