Message-Id:	<200006100652.JAA14812@mailgw1.netvision.net.il>
Date:	Sat, 10 Jun 2000 09:50:43 +0200
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From:	"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
To:	Prashant TR <prashant_tr AT yahoo DOT com>
CC:	djgpp AT delorie DOT com
In-reply-to:	<m3k8fymi6l.fsf@vsnl.net.in> (message from Prashant TR on 10 Jun
	2000 07:05:46 +0530)
Subject:	Re: far pointers
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> From: Prashant TR <prashant_tr AT yahoo DOT com>
> Newsgroups: comp.os.msdos.djgpp
> Date: 10 Jun 2000 07:05:46 +0530
> 
> > :) V86 mode was invented to provide compatibility with old 8086 stuff while
> > CPU is in PMode. DOS itself works normally in V86.
> 
> That's right. Usually, even plain DOS runs in V86 mode because the
> EMM386 driver switches to V86 when it gets installed.

V86 was invented because it allowed to use more than 640KB of memory,
by remapping some of the extended memory into the unused addresses
between 640K and 1MB.  Such remapping is impossible in real mode,
because the MMU is (effectively) inactive.  So they needed to have
protected mode, but with the normal real-mode addressing still
working.

However, this has nothing to do with PM programs and DOS coexisting
together.  PM programs still cannot run in V86 mode without the kind
of trickery that DJGPP does when it calls DOS.

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