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From:	kala AT sankya DOT com (Babu Kalakrishnan)
Newsgroups:	comp.os.msdos.djgpp
Subject:	DPMI Interrupt latency ?
Date:	Sat, 26 Jan 2002 16:14:34 +0530
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Could anyone tell me what is the order of delay (in clocks) required for
the CWSDPMI server to reflect a hardware interrupt from Real mode to the
protected mode handler ?

I need to write a Hardware Interrupt handler where latency is very
critical. Any suggestion regarding which DPMI server would provide me
the best latency figures would also be welcome. (The application need
not be portable - and I can specify the environment).

I would have liked to setup a Real mode interrupt handler as well to
reduce the latency - but the problem is that my Interrupt routine needs
random access to a 4MB buffer in extended memory. Would it be possible
to hack the DPMI server source code so that real mode handler can access
memory above 1MB using 32 bit pointers ? (the Flat mode)- in which case,
which Descriptor do I need to modify ?

Thanks in advance.

BK

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