beautypg.com

Hardware setup, 2 assigning irqs for expansion cards, Standard interrupt assignments – Asus CUV4X-LS User Manual

Page 28: Interrupt request table for this motherboard

background image

28

ASUS CUV4X-E User’s Manual

3. HARDWARE SETUP

Expansion Cards

3. H/W SETUP

3.7.2

Assigning IRQs for Expansion Cards

Some expansion cards need an IRQ to operate. Generally, an IRQ must be exclusively
assigned to one use. In a standard design, there are 16 IRQs available but most of
them are already in use, leaving 6 IRQs free for expansion cards.

IMPORTANT: If using PCI cards on shared slots, make sure that the drivers support
“Share IRQ” or that the cards do not need IRQ assignments. Conflicts arise between
the two PCI groups that makes the system unstable or cards inoperable.
The following table lists the default IRQ assignments for standard PC devices. Use
this table when configuring your system and for resolving IRQ conflicts.

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

Sound Card (sometimes LPT2)

6

14

Floppy Disk Controller

7*

15

Printer Port (LPT1)

8

3

System CMOS/Real Time Clock

9*

4

ACPI Mode when used

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.

Interrupt Request Table 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

shared

PCI slot 5

shared

PCI slot 6

shared

AGP Pro slot

shared

AMR slot

shared

Onboard Audio controller

shared

Onboard USB controller

shared

This manual is related to the following products: