Equipment List

 This identifies equipment and peripheral options which are installed
 and/or active.  It is returned from INT 11H (in AX) and can be found in
 the BIOS Data Area at 0040:0010.

 EquipmentListRec
  1 1 1 1 1 1
 ╓5┬4┬3┬2┬1┬0┬9┬8╥7┬6┬5┬4┬3┬2┬1┬0╖
 ║prt│ │j│ aux │ ║drv│vid│ram│n│d║
 ╙─┴─┴╥┴╥┴─┴─┴─┴╥╨─┴─┴─┴─┴─┴─┴╥┴╥╜  bits   mask
  ╚╦╝ ║ ║ ╚═╦═╝ ║ ╚╦╝ ╚╦╝ ╚╦╝ ║ ╚═►    0: 0001H disk drives are present
   ║  ║ ║   ║   ║  ║   ║   ║  ╚═══►    1: 0002H numeric coprocessor present
   ║  ║ ║   ║   ║  ║   ║   ╚══════►  2-3: 000eH motherboard RAM
   ║  ║ ║   ║   ║  ║   ╚══════════►  4-5: 0030H Initial/active video mode
   ║  ║ ║   ║   ║  ╚══════════════►  6-7: 00c0H total diskettes drives-1
   ║  ║ ║   ║   ╚═════════════════►    8: 0100H DMA present
   ║  ║ ║   ╚═════════════════════► 9-11: 0e00H RS232 serial ports
   ║  ║ ╚═════════════════════════►   12: 1000H game adapter present
   ║  ╚═══════════════════════════►   13: 2000H serial printer (PCjr)
   ╚══════════════════════════════►14-15: c000H printers installed

       bit 0  When this is 0, the computer has no diskette drives.
       bit 1  1 means that a numeric coprocessor is present.  This is not
              always reliable on older BIOSes.
    bits 2-3  motherboard memory: 01=16K; 10=32K; 11=64K+ (usually 00 on
              most modern PCs, so has no meaning)
              On PS/2s, bit 2 is 1 when a mouse is detected by the POST
    bits 4-5  Currently-active video adaptor.  It is one of:
                00=(reserved)   10=80-clm color
                01=40-clm color 11=TTL Monochrome
    bits 6-7  number of detected diskette drives -1:
                00=1; 01=2; 10=3; 11=4
       bit 8  1 = DMA hardware is present (not reliable)
   bits 9-11  detected RS-232 serial ports detected:
                000=0; 001=1...100=4...111=7
      bit 12  1=game adaptor (joystick) was detected by POST.
      bit 13  (on PCjr only) 1=serial printer attached
  bits 14-15  number of parallel printer ports:
                00=0; 01=1; 10=2; 11=3

   Notes: ■ This data word is often used to ascertain the active video
            adaptor and the location of video RAM.

            If (AX & 30H) == 30H then the Monochrome adapter is active
            and video RAM segment is at b000H, otherwise use b800H.  See
            Video Memory Layouts.

          ■ In general, the Equipment List word does not impart much useful
            information reliably.  For instance, even when bits 9-11
            indicate 4 serial ports, the computer may provide support for
            4 ports, but the hardware to handle only one or two is actually
            present.

See Also: BIOS Data Area
          INT 11H
                                    -♦-