INT 16 - AT.COM version 8/26/87 - API
AX = 8765h
BX = 4321h
CX = ??? or FFFFh
if CX = FFFFh
DX = number of event to remove or FFFFh
Return: ES:BX -> event record array
Note:   AT.COM is a resident scheduler by Bill Frolik

Format of event record:
Offset  Size    Description
00h    BYTE    in-use flag (00h free, 01h in use, FFh end of array)
01h    BYTE    day of date on which to trigger
02h    BYTE    month of date on which to trigger
03h    BYTE    trigger time, minute
04h    BYTE    trigger time, hour
05h    WORD    offset of command to be executed

168765BX4321 - AT.COM version 8/26/87 - API