SB IRQ \ VOGONS

SB IRQ

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First post, by swaaye

Posted on 2008-03-18, 01:15

swaaye Offline

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So, this has perplexed me for a while but I've just accepted it. UNTIL NOW! 😀

My old SBPro defaulted to IRQ 5. SB16 defaults to IRQ5, too. So, why does DOSBOX use 7?

Reply 1 of 4, by Great Hierophant

Posted on 2008-03-18, 01:25

Great Hierophant Offline

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Because the oldest SBPros and SBs defaulted to 7.

Reply 2 of 4, by mg55

Posted on 2008-03-18, 03:26

mg55 Offline

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I'm not certain, but I thought some very old games also assumed an SB IRQ of 7 and provided no way to tell the game otherwise.

Reply 3 of 4, by swaaye

Posted on 2008-03-18, 20:56

swaaye Offline

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Well if a game is hard-coded for IRQ 7, then it makes sense. Lots of games do seem to default to IRQ 5, however, but they are also re-configurable. And, of course, so is dosbox.conf so it doesn't matter whatsoever. Still an interesting choice to go with IRQ7 and I wondered why.