Int 10 Fn 1A00  - Video - Get Display Combination Code (ps,vga/mcga)       [V]

   AX = 1A00h

Return: AL = 1Ah if function was supported
       BL = active display code (see below)
       BH = alternate display code

See Also: AH=12h/BL=35h,AX=1A01h,AH=1Bh

Values for display combination code:
 00h   no display
 01h   monochrome adapter w/ monochrome display
 02h   CGA w/ color display
 03h   reserved
 04h   EGA w/ color display
 05h   EGA w/ monochrome display
 06h   PGA w/ color display
 07h   VGA w/ monochrome analog display
 08h   VGA w/ color analog display
 09h   reserved
 0Ah   MCGA w/ digital color display
 0Bh   MCGA w/ monochrome analog display
 0Ch   MCGA w/ color analog display
 FFh   unknown display type