User Guide

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75KAV/75KAV-X
2-9.7 IRQ DESCRIPTION
• Both ISA and PCI expansion cards may require IRQs. System IRQs are
available to cards installed in the ISA expansion bus first, then any remain-
ing IRQs are available to PCI cards. Currently, there are two types of ISA
cards.
• The original ISA expansion card design, now referred to as “Legacy” ISA
card, requires that you configure the card’s jumpers manually and then
install it in any available slot on the ISA bus. To see a map of your used and
free IRQs in Windows 98, the Control Panel in My Computer, contains a
System icon, which gives you a Device Manager tab. Double-Clicking on a
specific hardware device gives you a Resources tab which shows the Inter-
rupt number and address. Double-Clicking Computers to see all the inter-
rupts and addresses for your system. Make sure that no two devices use
the same IRQ or your computer will experience problems when those two
devices are in use at the same time.
IRQ 0 System Timer 1
IRQ Function Description Priority
IRQ 1 Keyboard Controller 2
IRQ 2 Programmable Interrupt N/A
IRQ 3 Serial Port (COM 2) 11
IRQ 4 Serial Port (COM 1) 12
IRQ 5 13
IRQ 6 Floppy Disk Controller 14
IRQ 7 Parallel Port (LPT1) 15
IRQ 8 Real Time Clock (RTC) 3
IRQ 9 4
IRQ 10 5
IRQ 11 6
IRQ 12 PS/2 Mouse Port 7
IRQ 13 Coprocessor 8
IRQ 14 Primary IDE Channel 9
IRQ 15 Secondary IDE Channel 10