Date: Sun, 11 Jun 2000 15:14:02 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Prashant TR <prashant_tr AT yahoo DOT com>
cc: pmode AT egroups DOT com, djgpp AT delorie DOT com
Subject: Re: far pointers
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On Sun, 11 Jun 2000, Prashant TR wrote:

> > > > 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.
> > > 
> > > I don't understand what V86 has to do with remapping of memory.
> > 
> > It turns on the MMU, without which this remapping is impossible.
> 
> No, I think you're mistaken. Switching to V86 does *not* turn on the
> MMU.

Let me say it more accurately: V86 allows MMU to be turned on while still 
retaining real-mode addressing.  And that was the main reason for its 
introduction, at the time.

> > In other words, having V86 doesn't make the PM and DOS coexistence any 
> > simpler, at least not by a large margin.
> 
> It doesn't make it simpler. Not a doubt about that. But it does add
> protection to your system.

That's another matter.  I was commenting on the sentence which said "V86 
means DOS and PM programs can coexist".