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INT 11h (17)             Read Equipment-List

    Returns a list of installed equipment on the system.

       On entry:      No parameters

       Returns:       AX         Equipment code

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                           Equipment code (AX)

  F E D C B A 9 8  7 6 5 4 3 2 1 0
  x x . . . . . .  . . . . . . . .  Number of printers installed
  . . x . . . . .  . . . . . . . .  Internal modem installed
  . . . x . . . .  . . . . . . . .  Game adapter installed? (always 1 on PCJr)
  . . . . x x x .  . . . . . . . .  Number of RS-232 ports
  . . . . . . . x  . . . . . . . .  Reserved
  . . . . . . . .  x x . . . . . .  Number of diskettes - 1 (i.e. 0=1 disk)
  . . . . . . . .  . . x x . . . .  Initial video mode (see below)
  . . . . . . . .  . . . . x . . .  Reserved
  . . . . . . . .  . . . . . x . .  Reserved
  . . . . . . . .  . . . . . . x .  Math coprocessor installed?
  . . . . . . . .  . . . . . . . x  1=diskettes present; 0=no disks present

                         Initial video mode

                   Value                 Meaning
                     00                   Reserved
                     01                   40 x 25 Color
                     10                   80 x 25 Color
                     11                   80 x 25 Monochrome

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       Notes:         The value returned in AX is the same as that stored
                      at memory location 0:0410h, 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.