Appendix D. Interrupt Request And Direct Memory Access Channel Assignments - IBM 6339 User Manual

Appendix D. Interrupt request and direct memory access
channel assignments
Table 4. IRQ channel assignments
IRQ
NMI
SMI
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Table 5. DMA channel assignments
DMA channel
0
1
2
3
4
5
6
7
© Copyright IBM Corp. 2001
The following tables list the IRQ and DMA channel assignments.
System resource
Critical system error
System-management interrupt for power management
Timer
Keyboard
Cascade interrupt from slave PIC
COM2 (some models only)
COM1
LPT2/audio (if present)
Diskette controller
LPT1
Real-time clock
Video, ACPI
MIDI/joystick (some models only)
Available to user
Mouse port
Math coprocessor
Primary IDE (if present)
Secondary IDE (if present)
Note: The default settings for COM 1 (IRQ 4), COM 2 (IRQ 3), and LPT 1 (IRQ 7)
can be changed to another IRQ.
Data width
8 bits
8 bits
8 bits
8 bits
16 bits
16 bits
16 bits
System resource
Open
Open
Diskette drive
Parallel port (for ECP or EPP)
Reserved (cascade channel)
Open
Open
Open
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