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.

IRQ assignments for this motherboard

 

PCI INTA

PCI INTB

PCI INTC

PCI INTD

PCIX1 slot (supports ZCR)

PIRQB4

PIRQB5

PIRQB9

PIRQB8

PCIX2 slot

PIRQB0

PIRQB1

PIRQB2

PIRQB3

PCIX3 slot

PIRQA4

PIRQA5

PIRQA6

PIRQA7

PCIX4 slot (riser slot A)

PIRQA0

PIRQA1

PIRQA2

PIRQA3

PCIX4 slot (riser slot B)

PIRQA4

PIRQA0

PIRQA1

PIRQA2

PCIX4 slot (riser slot C)

PIRQA5

PIRQA3

PIRQA1

PIRQA2

PCI1 slot

PIRQA

PIRQB

PIRQC

PIRQD

PCI2 slot

PIRQH

PIRQD

PIRQB

PIRQC

Onboard 82540 controller

PIRQE

—

—

—

Onboard 82544GC controller

PIRQA8

—

—

—

Onboard SCSI controller*

PIRQB8

PIRQB9

—

—

Onboard VGA controller

PIRQF

—

—

—

Onboard P64H2 controller

PIRQG

—

—

—

*Available only on PU-DLS model.

PIRQA~H are ICH3 interrupt inputs.

PIRQAn~Bn are P64H2 PCI A/B interrupt inputs.

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.

2-12

Chapter 2: Hardware information