From:	Prashant TR <prashant_tr AT yahoo DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: far pointers
Date:	10 Jun 2000 06:54:57 +0530
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Eli Zaretskii <eliz AT is DOT elta DOT co DOT il> writes:

>      In V86 mode, the 386 operates in real mode but allows some programs...
> 
> I believe you meant to say "protected mode".

Oh, yes! Thanks for the correction.

>   That means programs like DOS can coexist with protected-mode programs. 
> 
> I don't think V86 has anything to do with RM and PM programs coexisting. 
> perhaps I'm missing something in your reasoning.

That statement is right. Because without V86 mode, you wouldn't be
able to run any of your DOS programs without swicthing back to real
mode (which is terribly slow). And when a program run in V86 mode, it
*is* running in PMode at PL3. So this statement is right.

>   The memory management unit (MMU) on the 386 supports virtual memory
> 
> This is inaccurate: VM is not implemented by MMU, but by software that hooks
> the Page Fault exception and pages memory in and out as needed.

The word "support" is the key here. I meant that you *can* implement
VM on the 386. But I'll have that changed.

And btw, thanks for the feedback!

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