Contains a list of the hardware installed on the system.
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 (0=1 diskette)
. . . . . . . . . . x x . . . . Initial video mode (see below)
. . . . . . . . . . . . x x . . Reserved
. . . . . . . . . . . . . . x . Math coprocessor installed
. . . . . . . . . . . . . . . x 1=diskettes present, 0=no diskettes
Notes: Use INT 11h to access the equipment information via
The equipment list is initialized during the power-
For the IBM PC, XT, and PCjr, bits 2 and 3 lists the
amount of RAM installed on the system board in
increments of 16K. For example, 00 means 16K, while
Bit 2 on the XT-286 reports whether or not a
pointing device is installed.
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
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 would be to test it directly by
executing a math coprocessor instruction and then
checking to see if the instruction was executed.