3 Troubleshooting Your PC

Technical Information Needed for Troubleshooting

IRQs, DMAs, and I/O Addresses Used by Your PC

IRQs used by PC

IRQ0

system timer

 

IRQ1

keyboard

The IRQ, DMA, and I/O address

IRQ2

system cascade

mappings shown here are for a

IRQ3

free if not used for serial port 2

PC with a basic configuration.

IRQ4

free if not used for serial port 1

The resources used by your PC

IRQ5

free if not used for parallel port 2

may vary, depending upon

IRQ6

flexible disk drive controller

which accessory boards are

IRQ7

free if not used for parallel port 1

bundled with the PC.

IRQ8

real-time clock

 

IRQ9

available for PCI devices, if not used by ISA board

 

IRQ10

available for PCI devices, if not used by ISA board

 

IRQ11

available for PCI devices, if not used by ISA board

 

IRQ12

mouse

 

IRQ13

co-processor

 

IRQ14

integrated IDE hard disk drive controller

 

IRQ15

free if not used by second IDE controller

 

 

 

 

DMAs used by PC

DMA 0

free

 

DMA 1

free if not used for parallel port in Setup

 

DMA 2

flexible disk drive controller

 

DMA 3

free if not used for parallel port in Setup

 

DMA 4

used to cascade DMA channels 0-3

 

DMA 5

free

 

DMA 6

free

 

DMA 7

free

 

 

 

I/O Addresses used by PC

2Eh - 2Fh, integrated I/O controller

 

96h - 97h, “Little Ben”

 

E0h - E7h, HP reserved

 

170h - 177h, 376h IDE secondary channel

 

1F0h - 1F7h, 3F6h IDE primary channel

 

278h - 27Fh parallel port 2

 

2E8h - 2EFh serial port 4

 

2F8h - 2FFh serial port 2

 

378h - 37Fh parallel port 1

 

3B0h - 3DFh integrated video graphics controller

 

3E8h - 3EFh serial port 3

 

3F0h - 3F5h, 3F7h integrated flexible disk controller

 

3F8h - 3FFh serial port 1

 

496h - 497h HP reserved

 

678h - 67Dh parallel port if ECP mode is selected

 

778h - 77Dh parallel port if ECP mode is selected

 

 

 

 

 

 

 

 

51

Page 61
Image 61
HP HEWLET VECTRA VA 6/XXX manual IRQs, DMAs, and I/O Addresses Used by Your PC