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

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 holer for PCI steering

10*

5

IRQ holer for PCI steering

11*

6

IRQ holer 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.

1.8.2 IRQ assignments for this motherboard

 

INT A

INT B

INT C

INT D

PCI slot 1

shared

-

-

-

PCI slot 2

-

shared

-

-

PCI slot 3

-

-

shared

-

PCI slot 4

-

-

-

used

Internal USB 2.0 controller

shared

shared

shared

shared

10/100 LAN

-

shared

-

-

AGP slot

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