IBM NetVista, Техническое руководство

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© Copyright IBM Corp. 2000
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Appendix C. IRQ and DMA channel assignments
The following figures list the IRQ and DMA channel assignments.
Note: The default settings for COM 1 (IRQ 4), COM 2 (IRQ 3), and LPT 1 (IRQ 7) can
be changed to another IRQ.
Table 35. IRQ channel assignments
IRQ System resource
NMI Critical system error
SMI System-management interrupt for power management
0 Timer
1 Keyboard
2 Cascade interrupt from slave PIC
3 COM2 (some models only)
4 COM1
5 LPT2/audio (if present)
6 Diskette controller
7 LPT1
8 Real-time clock
9 Video, ACPI
10 MIDI/joystick (A20 models only)
11 Available to user
12 Mouse port
13 Math coprocessor
14 Primary IDE (if present)
15 Secondary IDE (if present)
Table 36. DMA channel assignments
DMA channel Data width System resource
0 8 bits Open
1 8 bits Open
2 8 bits Diskette drive
3 8 bits Parallel port (for ECP or EPP)
4 Reserved (cascade channel)
5 16 bits Open
6 16 bits Open
7 16 bits Open