Standard interrupt assignments
IRQ | Priority | Standard Function |
0 | 1 | System Timer |
1 | 2 | Keyboard Controller |
2 | N/A | Programmable Interrupt |
4* | 12 | Communications Port (COM1) |
5* | 13 | Sound card (sometimes LPT2) |
|
|
|
6 | 14 | Floppy Disk Controller |
7* | 15 | Printer Port (LPT1) |
|
|
|
8 | 3 | System CMOS/Real Time Clock |
9* | 4 | ACPI Mode when used |
|
|
|
10* | 5 | IRQ Holder for PCI Steering |
11* | 6 | IRQ Holder for PCI Steering |
|
|
|
12* | 7 | PS/2 Compatible Mouse Port |
13 | 8 | Numeric Data Processor |
|
|
|
14* | 9 | Primary IDE Channel |
15* | 10 | Secondary IDE Channel |
|
|
|
*These IRQs are usually available for ISA or PCI devices.
IRQ assignments for this motherboard
| INT A | INT B | INT C | INT D | INT E |
PCI slot 1 | shared | ||||
PCI slot 2 | shared | ||||
PCI slot 3 | shared | ||||
PCI slot 4 | shared | ||||
PCI slot 5 | shared | ||||
Onboard 1394 | shared | ||||
Serial ATA | shared | ||||
AGP slot | shared | ||||
Onboard Audio | shared |
When using PCI cards on shared slots, ensure that the drivers support “ShareIRQ” or that the cards do not need IRQ assignments. Otherwise, conflicts willarise between the two PCI groups, making the system unstable and the cardinoperable.
Chapter 1: Product introduction |