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7-3
Compaq Professional Workstation AP400 Maintenance and Service Guide
Table 7-2
System Interrupts
Hardware IRQ
System Function
IRQ 0
System timer
IRQ 1
Keyboard (Not on ISA Bus)
IRQ 2
Used by programmable interrupt controller
IRQ 3
Serial Port (COM 2)
IRQ 4
Serial Port (COM 1)
IRQ 5
ESS sound chip
IRQ 6
Diskette Drive
IRQ 7
Parallel Port (LPT 1)
IRQ 8
Real-time clock
IRQ 9
Unavailable (used for ACPI support)
IRQ 10
Unused
IRQ 11
PCI Interrupts
IRQ 12
Mouse
IRQ 13
Non-catastrophic errors / CPU error
IRQ 14
Primary IDE Controller
IRQ 15
Secondary IDE Controller