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From: nebo <nebo AT linetap DOT com>
Organization: neboland
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Newsgroups: comp.os.msdos.djgpp
Subject: Re: Timer interrupt
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Date: Sun, 05 Jul 1998 01:09:12 GMT
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Matt Barker wrote:
> 
> > I don't know the answer to your question, but I have answers to
> > questions you didn't ask:
> >
> > OldTimerHandler() sends an EOI on its own, so you shouldn't do it in
> > your handler when you call OldTimerHandler(). And IIRC you shouldn't
> > call Int 1C manually, because that's done by OldTimerHandler() as well -
> > and I guess you set Factor so that OldTimerHandler() is called just as
> > often as it is normally called.
> 
> Won't OldTimerHandler() end with an iret instruction though, in which case
> it will not return to my handler???  It certainly seemed to work OK.

	It will end with an iret instruction, but...
	IRET only pops IP, CS and the flags, and then returns to the
	interrupted program(your handler).


-- 



        Nb
        nebo AT LTS                MajorNet
        nebo AT linetap DOT com        Internet


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