Standard interrupt assignments

I R Q

Priority

Standard Function

0

1

System Timer

 

 

 

1

2

Keyboard Controller

 

 

 

2

–

Re-direct to IRQ#9

 

 

 

3

11

IRQ holder for PCI steering*

 

 

 

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

 

 

 

* These IRQs are usually available for ISA or PCI devices.

IRQ assignments for this motherboard

 

A

B

C

D

E

F

G

H

 

PCI slot 1

shared

—

—

—

—

—

—

—

 

PCI slot 2

—

shared

—

—

—

—

—

—

 

IDE (0, 0f, 0)

—

shared

—

—

—

—

—

—

 

USB controller 1

shared

—

—

—

—

—

—

—

 

USB controller 2

—

—

shared

—

—

—

—

—

 

USB controller 3

—

used

—

—

—

—

—

—

 

USB controller 4

—

—

—

shared

—

—

—

—

 

USB 2.0 controller

—

—

shared

—

—

—

—

—

 

AC’97

—

—

shared

—

—

—

—

—

 

Ethernet

shared

—

—

—

—

—

—

—

 

AGP

shared

—

—

—

—

—

—

—

 

PCIE x1

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.

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Chapter 1: Product introduction