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From: dubner@hpspkla.spk.hp.com (Joe Dubner)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Re: PC Interrupts, urgent request
Message-ID: <8750001@hpspkla.spk.hp.com>
Date: 6 Jan 91 18:09:01 GMT
References: <45739@cci632.UUCP>
Organization: Hewlett Packard Company, Spokane, Wa.
Lines: 14

> The initialization routine sets up the interrupt vector using (I am using
> the MS Quick C compiler) dos_getvect() and dos_setvect(). I do the
> dos_getvect() to save the original IRQ5 handler. I then read the OCW1 control

I don't know a lot about the interrupt controller chip in the PC, and
know even less about MS Quick C, but I'd be willing to bet good money
that dos_getvect() works on software interrupts, not hardware IRQ lines.
When you do a dos_getvect() on "5", you're saving the INT 05h vector,
which is used to sense the PrtSc key.

Lots of luck.


... Joe