Int 1A Fn FF  - At&t 6300 - Set Time And Date                              [b]

   AH = FFh
   BX = day count (0 = Jan 1, 1984)
   CH = hour
   CL = minute
   DH = second
   DL = hundredths

Return: ???

See Also: AX=CCCCh/BX=CCCCh,AH=FEh,INT 21/AH=2Bh"DATE",INT 21/AH=2Dh