IRQ-related questions \ VOGONS

IRQ-related questions

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First post, by iulianv

Posted on 2011-05-09, 10:10

iulianv Offline

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Yesterday I experimented some really weird issues after relocating a 486 system in a new case and reinstalling DOS and WfW on it - the NIC that I was previously using in the same system doesn't work anymore (doesn't seem to be able to send or receive traffic), and two other NICs that I have behave erratically (after each reboot they work in WfW but if I run their setup utilities I get "IRQ fail" or "IRQ conflict" and they don't work in WfW until next reboot) - so today I'm reading about IRQ, DMA and I/O resources...

Two questions:

- what software can I use (in DOS or Win3x) to get a list of (un)used IRQ numbers?

- I've seen on many VLB video cards a jumper for IRQ2/9 setting; if I close it I assume the card will use IRQ9, but what IRQ will the card use if I leave the jumper open? IIRC I had at least one card that would only POST in one of the situations (jumper closed or open, I can't remember exactly)...

Reply 1 of 3, by Dominus

Posted on 2011-05-09, 10:14

Dominus Offline

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Norton utilities has some software that shows irq in both windows and dos

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Reply 2 of 3, by iulianv

Posted on 2011-05-12, 05:12

iulianv Offline

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Indeed it has... I also found Quarterdeck Manifest - they pretty much detected the same IRQ configuration, but it was the difference between their output that helped me sort out the problem.

Every once in a while one of them would show that the ASUSCD driver was using IRQ15 (I only use have one IDE channel of the controiller enabled, with both the HDD and the CD drive on it), so I went to the driver's README file for details about interrupt handling, and found out that my chipset (OPTi 82C895) was not on the list of supported chipsets. I uninstalled the ASUS driver and replaced it with something "generic", and the "bouncing IRQ" issue disappeared (adding the CD drive was the only difference between before and after relocating the system into a new case).

Now, to put back the sound card and go figure out some more issues about the video card... does anyone know a good DOS software for testing video RAM? 😀 NU has one, but a second "opinion" is always useful (Manifest says I have 1280KB on my 2-meg Trident 😕 ).

Reply 3 of 3, by Davros

Posted on 2011-05-12, 08:43

Davros Offline

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maybe msd.exe (havnt used it in years)
its part of dos btw

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