Computer Hardware User Manual

Chapter 3 Signals and Pinout Tables
48 Reference Manual COM 830
Interrupt Request (IRQ) Lines
In PIC mode, the PCI bus interrupt lines can be routed to any free IRQ.
Table 3-27. IRQ Lines in PIC mode
IRQ# Available Typical Interrupt Source Connected to Pin
0 No Counter 0 Not applicable
1 No Keyboard Not applicable
2 No Cascade Interrupt from Slave PIC Not applicable
3 Yes IRQ3 via SERIRQ or PCI BUS INTx
4 Yes IRQ4 via SERIRQ or PCI BUS INTx
5 Yes IRQ5 via SERIRQ or PCI BUS INTx
6 Yes IRQ6 via SERIRQ or PCI BUS INTx
7 Yes IRQ7 via SERIRQ or PCI BUS INTx
8 No Real-time Clock Not applicable
9 Note 2 SCI / Generic IRQ9 via SERIRQ or PCI BUS INTx
10 Yes IRQ10 via SERIRQ or PCI BUS INTx
11 Yes IRQ11 via SERIRQ or PCI BUS INTx
12 Yes IRQ12 via SERIRQ or PCI BUS INTx
13 No Math processor Not applicable
14 Note 1 IDE Controller 0 (IDE0) / Generic IRQ14 or PCI BUS INTx
15 Note 1 IDE Controller 1 (IDE1) / Generic IRQ15 or PCI BUS INTx
NOTE If the ATA/IDE configuration is set to enhanced mode in BIOS setup (serial ATA
and parallel ATA native mode operation), IRQ14 and 15 are free for PCI/LPC
bus.
In ACPI mode, IRQ9 is used for the SCI (System Control Interrupt). The SCI can
be shared with a PCI interrupt line.
Table 3-28. IRQ Lines in APIC mode
IRQ# Available Typical Interrupt Source Connected to Pin / Function
0 No Counter 0 Not applicable
1 No Keyboard Not applicable
2 No Cascade Interrupt from Slave
PIC
Not applicable
3 Yes IRQ3 via SERIRQ
4 Yes IRQ4 via SERIRQ
5 Yes IRQ5 via SERIRQ
6 Yes IRQ6 via SERIRQ
7 Yes IRQ7 via SERIRQ
8 No Real-time Clock Not applicable