Asus A7Pro Motherboard DIY Troubleshooting Guide - Page 30

Assigning IRQs for Expansion Cards - sound driver

Page 30 highlights

3. H/W SETUP Expansion Cards 3. HARDWARE 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. If your motherboard has PCI audio onboard, an additional IRQ will be used. If your motherboard also has MIDI enabled, another IRQ will be used, leaving 4 IRQs free. 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 will arise between the two PCI groups that will make 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 0 1 1 2 2 N/A 3* 11 4* 12 5* 13 6 14 7* 15 8 3 9* 4 10* 5 11* 6 12* 7 13 8 14* 9 15* 10 Standard Function System Timer Keyboard Controller Programmable Interrupt Communications Port (COM2) Communications Port (COM1) Sound Card (sometimes LPT2) Floppy Disk Controller Printer Port (LPT1) System CMOS/Real Time Clock ACPI Mode when used IRQ Holder for PCI Steering IRQ Holder for PCI Steering PS/2 Compatible Mouse Port Numeric Data Processor Primary IDE Channel Secondary IDE Channel *These IRQs are usually available for PCI devices. Interrupt Request Table for this Motherboard PCI slot 1 PCI slot 2 PCI slot 3 PCI slot 4 PCI slot 5 AGP Pro slot Onboard USB controller Onboard audio/AMR INT-A shared - - - - shared - - INT-B - shared - - - shared - - INT-C - - shared - - - - shared INT-D - - - shared shared - shared - 30 ASUS A7PRO User's Manual

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30
ASUS A7PRO 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 exclu-
sively 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. If your
motherboard has
PCI
audio onboard, an additional IRQ will be used. If your moth-
erboard also has
MIDI
enabled, another IRQ will be used, leaving 4 IRQs free.
IMPORTANT:
If using PCI cards on shared slots, make sure that the drivers sup-
port “Share IRQ”
or that the cards do not need IRQ assignments. Conflicts will
arise between the two PCI groups that will make the system unstable or cards inop-
erable.
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 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
AGP Pro slot
shared
shared
Onboard USB controller
shared
Onboard audio/AMR
shared