From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: interrupt priority
Date:	Fri, 17 Mar 2000 10:49:58 +0200
Organization:	NetVision Israel
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Damian Yerrick wrote:
> 
> On Thu, 16 Mar 2000 12:01:45 +0200 (IST), Eli Zaretskii
> <eliz AT is DOT elta DOT co DOT il> wrote:
> 
> >Using IRQ 5 is not a good thing anyway, since the interrupt associated
> >with it, Int 0Dh, is in conflict with the GPF exception.  If your
> >program causes GPFs (e.g., if it uses signals), you could lose
> >interrupts as a result.
> 
> Are you saying preinstalled sound cards (which default to IRQ 5 if
> the user does not void the computer's warranty by opening the case)
> are incompatible with signals?

This discussion was not about compatibility (the OP's interrupt handler
hooked to IRQ 5 *did* work), it is about supporting interrupts at a high
rate.

What I was saying is that, due to the overhead incurred by exceptions being
reflected as interrupts (because they share the same numbers), using IRQ 5
for hardware interrupts in a protected-mode program might begin losing
interrupts at a lower rate than it would for another IRQ.

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