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Int 11h                 Read Equipment-List

    Returns a list of installed equipment on the system.

        Entry   No parameters

        Return  AX = Equipment code

    ------------------------------------------------------------------

    Equipment code (AX)

    FEDCBA98  76543210
    xx......  ........  Number of printers installed
    ..x.....  ........  Internal modem installed
    ...x....  ........  Game adapter installed? (always 1 on PCJr)
    ....xxx.  ........  Number of RS-232 ports
    .......x  ........  Reserved
    ........  xx......  Number of diskettes - 1 (i.e. 0=1 disk)
    ........  ..xx....  Initial video mode
                        00   Reserved
                        01   40 x 25 Color
                        10   80 x 25 Color
                        11   80 x 25 Monochrome
    ........  ....x...  Reserved
    ........  .....x..  Reserved
    ........  ......x.  Math coprocessor installed?
    ........  .......x  1=diskettes present; 0=no disks present

    ------------------------------------------------------------------

    The value returned in AX is the same as that stored at memory
    location 0040h:0010h, which is initialized during the power-up
    tests.

    For the IBM PC, XT, and PCjr, bits 2 and 3 used to list the amount
    of RAM installed on the system board in increments of 16K. For
    example, 00 meant 16K, while 11 meant 64K.

    Bit 0 indicates only whether the system has one or more diskette
    drives. Refer to bits 6 and 7 to find out how many diskettes are
    actually present. To determine the number of hard disks installed,
    use Int 13h, Service 8.

    If the DIP switches for PCs and XTs are not set correctly
    reflecting the presence of a math coprocessor, then bit 1 (math
    coprocessor present) may be incorrect. A better test for the math
    coprocessor is to test it directly by executing a math coprocessor
    instruction and then checking to see if the instruction was
    executed.