3. HARDWARE SETUP 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 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 DMA Channels 3.
H/W SETUP *These IRQs are usually available for ISA or PCI devices. Both ISA and PCI expansion cards may require IRQs. System IRQs are available to cards installed in the ISA expansion bus first, then any remaining 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 cards, re- quires 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 icon in My Computer , contains a System icon, which gives you a Device Manager tab.
Double-clicking on a specific hardware device gives you the Resources tab which shows the Interrupt number and address. Double-click Computer to see all the interrupts 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. To simplify this process, this motherboard complies with the Plug and Play (PNP) specification which was developed to allow automatic system configuration when- ever a PNP-compliant card is added to the system. For PNP cards, IRQs are as- signed automatically from those available. ASUS P3C-L / P3C-S / P3C-LS User’s Manual 39