IBM 6792 User Guide - Page 79

Appendix D. Interrupt request and direct memory access channel assignments

Get IBM 6792 - NetVista M41 - 256 MB RAM PDF manuals and user guides
UPC - 087944764670
View all IBM 6792 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 79 highlights

Appendix D. Interrupt request and direct memory access channel assignments The following tables list the IRQ and DMA 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 System resource Critical system error System-management interrupt for power management Timer Keyboard Cascade interrupt from slave PIC COM2 (some models only) COM1 Available to user Diskette controller LPT1 Real-time clock Video, ACPI Available to user 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. Table 5. DMA channel assignments DMA channel 0 1 2 3 4 5 6 7 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 © Copyright IBM Corp. 2001 67

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
Appendix D. Interrupt request and direct memory access
channel assignments
The following tables list the IRQ and DMA channel assignments.
Table 4. 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
Available to user
6
Diskette controller
7
LPT1
8
Real-time clock
9
Video, ACPI
10
Available to user
11
Available to user
12
Mouse port
13
Math coprocessor
14
Primary IDE (if present)
15
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.
Table 5. 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
© Copyright IBM Corp. 2001
67