Int 14 Fn FC  - Ibm/yale Ebios Serial I/o - Read Character, No Wait        [S]

   AH = FCh
   DX = port (00h-03h)

Return: AH = RS232 status bits (see #0230 at AH=03h)
   AL = character

See Also: AH=02h,AH=0Ch,AX=FF02h