2 System Board

Assigned Device Interrupts

Although the Setup program can be used to change some of the settings, the following address map is not completely BIOS dependent, but is determined partly by the operating system. Note that some of the interrupts are allocated dynamically.

 

APIC Controller

Interrupt Signalling on

Interrupt Source

 

 

 

 

of

Input

(PIC mode)1

(APIC

 

 

device

modes)

 

 

 

 

 

 

 

 

INTA - PCI slot 3 (64/66)

P64H

IRQ0

BT_INT

APIC bus

 

 

 

 

 

INTB - PCI slot 3 (64/66)

P64H

IRQ1

BT_INT

APIC bus

 

 

 

 

 

INTC - PCI slot 3 (64/66)

P64H

IRQ2

BT_INT

APIC bus

 

 

 

 

 

INTD - PCI slot 3 (64/66)

P64H

IRQ3

BT_INT

APIC bus

 

 

 

 

 

INTA - PCI slot 4 (64/66)

P64H

IRQ4

BT_INT

APIC bus

 

 

 

 

 

INTB - PCI slot 4 (64/66)

P64H

IRQ5

BT_INT

APIC bus

 

 

 

 

 

INTC - PCI slot 4 (64/66)

P64H

IRQ6

BT_INT

APIC bus

 

 

 

 

 

INTD - PCI slot 4 (64/66)

P64H

IRQ7

BT_INT

APIC bus

 

 

 

 

 

INTA - onboard SCSI controller

P64H

IRQ8

BT_INT

APIC bus

 

 

 

 

 

AGP - INTA, PCI Slot 1 - INTC, PCI

ICH

INTA

INT

APIC bus

Slot 2 - INTA, PCI Slot 5 - INTB

 

 

 

 

 

 

 

 

 

PCI Audio - INTA, AGP - INTB, PCI

ICH

INTB

INT

APIC bus

Slot 1 - INTD, PCI Slot 2 - INTB,

 

 

 

 

PCI Slot 5 - INTC

 

 

 

 

 

 

 

 

 

BT_INT, PCI Slot 1 - INTA, PCI

ICH

INTC

INT

APIC bus

Slot 2 - INTC, PCI Slot 5 - INTD

 

 

 

 

 

 

 

 

 

USB - INTA, PCI Slot 1 - INTB, PCI

ICH

INTD

INT

APIC bus

Slot 2 - INTD, PCI Slot 5 - INTA

 

 

 

 

 

 

 

 

 

Device on Primary IDE Channel

ICH

IRQ14

INT

APIC bus

 

 

 

 

 

Device on Secondary IDE Channel

ICH

IRQ15

INT

APIC bus

 

 

 

 

 

Serial Interrupt from Super I/O

ICH

SERIRQ

INT

APIC bus

 

 

 

 

 

1.In PIC mode, the Interrupts signaled to the P64H are chained as INTC to the ICH.

There are three major interrupt modes available:

PIC mode: This mode uses only the “Legacy” interrupt controllers, so that only one processor can be supported. Because this system has dual processor capability, this mode is not chosen by default by Windows NT. However, during Windows NT installation, you have the possibility of selecting this mode.

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