Asus INTEL TUSL2 - Manual (Page 29)

ASUS TUSL2 User’s Manual 29
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.
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 enabled
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
Interrupt requests are shared as shown by the following table:
A B C D E F G H
PCI slot 1 — — — — — shared — —
PCI slot 2 — — — — — — shared —
PCI slot 3 — — — — — — — shared
PCI slot 4 — — — — shared — — —
PCI slot 5 — — — — — shared — —
PCI slot 6 — — used — — — — —
Onboard VGA shared — — — — — — —
Onboard USB controller HC0 — — — used — — — —
Onboard USB controller HC1 — — — — — — — shared
AGP Pro shared — — — — — — —
CNR LAN — — — — shared — — —
CNR Audio/Modem — used — — — — — —
Onboard Promise — — — — — — shared —
Onboard Audio — — — — — shared — —
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 inoperable.