Equipment Byte - IBM Personal System/2 60 Technical Reference

Equipment Byte (Hex 014): The equipment byte defines the basic
equipment in the system for the power-on diagnostic tests.
Bit Function
7, 6
Number of Diskelte Drives
5, 4 Display Operating Mode
3, 2 Reserved
1 Math Coprocessor Presence
o
Diskelte Drive Presence
Figure 3-18. Equipment Byte
Bits 7, 6 These bits indicate the number of diskette drives installed,
as shown In the following figure.
Bits Numberot
76
Disken. Drive.
00
One Drive
01 Two Drives
10
Reserved
1 1
Reserved
Figure 3-19. Equipment Byte (Bits 7, 6)
Bits 5,4 These bits indicate the operating mode of the display
attached to the video port, as shown in the following
figure.
Bits DI.play
5 4 OperaUng Mode
00 Reserved
o
1 4O-Column Mode
1 0 8O-Column Mode
1 1 Monochrome Mode
Figure 3-20. Equipment Byte (Bits 5, 4)
Bits 3, 2
Reserved.
Bit 1 When set to 1, this bit indicates that a math coprocessor is
installed.
Bit 0 When set to 1, this bit indicates that a diskette drive is
installed.
Model 60 System Board 3-19