4 Troubleshooting Your PC
Technical Information
90
English
IRQs, DMAs, and I/O Addresses Used by Your PC
IRQs used by PC
The IRQ, DMA, and I/O
address mappings
shown here are for
guidance only. The
resources used by your
PC may vary,
depending upon which
accessory boards are
installed in the PC.
IRQ0
PIIX4e system timer
IRQ1
NS309 keyboard controller
IRQ2
Used to cascade
IRQ3
NS309 COM2, COM4
IRQ4
NS309 COM1, COM3
IRQ5
Free
IRQ6
NS309 flexible disk drive controller
IRQ7
NS309 LPT
IRQ8
PIIX4e RTC
IRQ9
Free (if not used by video card)
IRQ10
Free (if not used by onboard USB controller)
IRQ11
Free
IRQ12
NS309 mouse
IRQ13
Numeric coprocessor
IRQ14
PIIX4e IDE channel 1
IRQ15
PIIX4e IDE channel 2
DMAs
used by PC
DMA 0
free
DMA 1
free
DMA 2
NS309 flexible disk drive controller
DMA 3
NS309 LPT ECP
DMA 4
used to cascade DMA channels 0-3
DMA 5
free
DMA 6
free
DMA 7
free
bird-up4.fb4 Page 90 Thursday, June 18, 1998 5:59 PM