IBM Personal System/2 65 SX - Diskette-Drive-Type Bits (Bits 3-0); Equipment Byte

Bits3-0 These bits indicate the second diskette-drive type, as
shown in the following table.
Bits
3210 Function
0000 No drive present
0001 Double-sided diskette drive (48 tracks per inch, 360KB)
0011 High-capacity diskette drive (720KB)
0100 High-density diskette drive (1.44MB)
Note: All combinations that are not shown are reserved.
Figure 3-18. Diskette-Drive-Type Bits (Bits 3-0)
Reserved Bytes (Hex 011 through 013): These bytes are reserved.
Equipment Byte (Hex 014): This byte defines the basic equipment in
the system for the power-on diagnostic tests.
Bit Function
7,6 Number of Diskette Drives
5,4 Display Operating Mode
3,2 Reserved
1 Math Coprocessor Presence
0 Diskette-Drive Presence
Figure 3-19. Equipment Byte
Bits 7,6 These bits indicate the number of diskette drives installed,
as shown in the following table.
Bits Number of
76 Diskette Drives
00 One Drive
01 Two Drives
10 Reserved
11 Reserved
Figure 3-20. Number of Diskette-Drive Bits
Model 65 System Board — October 1990 3-19