1.8.3Interrupt assignments
IRQ | Priority | Standard function |
0 | 1 | System Timer |
1 | 2 | Keyboard Controller |
2 | – | Redirect to IRQ#9 |
4 | 12 | Communications Port (COM1)* |
5 | 13 | IRQ Holder for PCI Steering* |
6 | 14 | Floppy Disk Controller |
7 | 15 | Printer Port (LPT1)* |
8 | 3 | System CMOS/Real Time Clock |
9 | 4 | IRQ Holder for PCI Steering* |
10 | 5 | IRQ Holder for PCI Steering* |
11 | 6 | |
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
| A | B | C | D |
PCI slot 1 | – | shared | – | – |
PCI slot 2 | – | – | shared | – |
PCI slot 3 | – | – | – | shared |
PCI slot 4 | shared | – | – | – |
PCIe x1 slot | Fixed | Fixed | Fixed | Fixed |
Onboard USB controller 1 | shared | – | – | – |
Onboard USB controller 2 | – | – | shared | – |
Onboard USB controller 3 | – | shared | – | – |
Onboard USB controller 4 | – | – | – | shared |
Onboard USB 2.0 contoller | – | – | shared | – |
Onboard LAN | shared | – | – | – |
Onboard audio | – | shared | – | – |
When using PCI cards on shared slots, ensure that the drivers support “Share IRQ” or that the cards do not need IRQ assignments. Otherwise, conflicts will arise between the two PCI groups, making the system unstable and the card inoperable.
ASUS |