PC i/o - Adresses & IRQ
Les i/o du PC - Adresses et IRQ

by Robert BILLON

Last update


It may happen than one wishes to add a peripheral or an extension board to his PC. It is at that time that one begin to ask oneself the excrutiating question of the adresses and interrupts to use in order to avoid conflicts with the existing ones. The table here after would help to make the good choice.

For a given peripheral, the first adress is the base adress, the second is the hight limit of the adresses zone used by this peripheral.

Avant propos   

Il arrive que l'on souhaite ajouter un périphérique ou une carte d'extension dans son PC. C'est à ce moment là que l'on commence à se poser la question cruciale des adresses et interruptions à utiliser afin d'éviter les conflits avec l'existant. Le tableau ci-après devrait aider à faire le bon choix.

Pour un périphérique donné, la première adresse est l'adresse de base, la deuxième est la limite haute de la zone d'adresses utilisées par ce périphérique.



000-01F       DMA controler 1
020-03F       interrupt controler
040-05F       timer
060-06F       keyboard
070-07F       real-time clock
080-09F       DMA page register
0A0-0BF       interrupt controler 2
0C0-0DF       DMA controler
0F0-0FF       math coprocessor
100-1EF       not usable
1F0-1F8       fixed disk
200-207       game port
220-          factory default for Sound Blaster sound cards, 
               (possible custom adresses from 210 to 270)
278-27F       parallel printer port 2 (dos LPT2: , Linux /dev/lp1)
2E8-2EF       may be used for dos COM4: , Linux /dev/ttyS3
2F8-2FF       serial port 2 (dos COM2: , Linux /dev/ttyS1)
300-31F       prototype card
360-36F       reserved
378-37F       parallel printer port 1 (dos LPT1: , Linux /dev/lp0)
388-          Adlib sound card
3B0-3BF       monochrome display
3C0-3CF       reserved
3D0-3DF       color graphics display
3E8-3EF       may be used for dos COM3: , Linux /dev/ttyS2
3F0-3F7       diskette controler
3F8-3FF       serial port 1 (dos COM1: , Linux /dev/ttyS0)

2.  IRQ

IRQ           DEVICE

0             timer
1             keyboard
2             used as input from interrupt controler 2,
               (IRQ from 8 to 15) 
3             COM2:
4             COM1:
5             LPT2: (as LPT2: do not use an IRQ
               it can be used for another device,
               factory default for Sound Blaster sound cards)
6             diskette controler
7             LPT1: (as LPT1: do not use an IRQ
               it can be used for another device, e.g. sound card)
8             real-time clock
9             free for user
10            free for user
11            free for user (e.g. SCSI)
12            bus mouse (free if no bus mouse present, e.g. for network)
13            math coprocessor
14            fixed disk
15            free for user (e.g. network)               

File: pcio.html - Robert L.E.Billon, 2000-03-28 - Last update: 2010-11-04