1-20
Chapter 1: Product introduction
1.8.3 Interrupt assignments
* These IRQs are usually available for ISA or PCI devices.
IRQ assignments for this motherboard
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.
Standard interrupt assignments
IRQ
Priority
Standard Function
0
1
System Timer
1
2
Keyboard Controller
2
N/A
Re-direct to IRQ#9
3
11
Communications Port (COM2)*
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
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
A
B
C
D
E
F
G
H
PCI slot 1
—
—
—
—
—
—
used
—
PCI slot 2
—
—
—
—
—
used
—
—
PCI slot 3
—
shared
—
—
—
—
—
—
Onboard USB controller 1
shared
—
—
—
—
—
—
—
Onboard USB controller 2
—
—
—
used
—
—
—
—
Onboard USB controller 3
—
—
used
—
—
—
—
—
Onboard USB controller 4
shared
—
—
—
—
—
—
—
Onboard USB 2.0 controller
—
—
—
—
—
—
—
shared
Onboard LAN
—
—
—
—
—
—
—
shared
Onboard audio
—
shared
—
—
—
—
—
—
Onboard VGA
shared
—
—
—
—
—
—
—