1.8.1

Standard interrupt assignments

IRQ

 

Priority

Standard Function

0

 

1

System Timer

1

 

2

Keyboard Controller

2

 

N/A

Programmable Interrupt

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

Advance AC’97 CODEC

 

 

 

 

11*

 

6

Standard PCI Graphics Adapter (VGA)

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.

1.8.2 IRQ assignments for this motherboard

 

A

B

C

D

E

F

G

H

PCI slot 1

—

—

shared

—

—

—

—

—

 

PCI slot 2

—

—

—

shared

—

—

—

—

 

PCI slot 3

—

—

—

—

—

—

shared

—

 

PCI slot 4

—

—

—

—

—

shared

—

—

 

AGP slot

—

—

—

—

shared —

—

—

 

Onboard USB controller HC1 shared

—

—

—

—

—

—

—

 

Onboard USB controller HC2

—

—

—

shared

—

—

—

—

 

Onboard USB controller HC3

—

—

shared

—

—

—

—

—

 

Onboard USB 2.0 controller

—

—

—

—

—

—

— shared

 

Onboard LAN

—

—

—

—

—

—

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 arise between the two PCI groups making the system unstable and the card inoperable.

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Chapter 1: Product introduction