Appendix C. IRQ and DMA-Channel Assignments
This appendix lists the interrupt-request (IRQ) and direct-memory-access
(DMA)-channel assignments for your system unit for the Model 140 and Model 240.
Note: If you install ISA adapters in your Model 140 or Model 240 system unit, be
sure that no interrupts or DMA channels conflict with existing resources. For
example, do not set an ISA adapter to use interrupt (IRQ) 6, because IRQ6 is
used by the diskette drive.

IRQ Assignments

The following table shows the interrupt-request assignments.
IRQ Description
0 Interval timer
1 Keyboard
2 Cascade from controller 2 (Not available)
3 Serial port 2
4 Serial port 1
5 Available for ISA bus if not used for audio
6 Diskette drive
7 Parallel port 1 or Audio
8 Real-time clock
9 Available for ISA bus
10 Available for ISA bus
11 Available for ISA bus
12 Available for ISA bus if not used for mouse
13 Scatter Gather
14 Available for ISA bus
15 Available for ISA bus if not used for tablet port
Copyright IBM Corp. 1996, 1998 C-1