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From: "Serge A. Babkin" <babkin@hq.icb.chel.su>
Message-Id: <199610281721.WAA26270@hq.icb.chel.su>
Subject: Re: DOS emulation (was Re: Networking in PCEMU (1/2))
To: luigi@labinfo.iet.unipi.it (Luigi Rizzo)
Date: Mon, 28 Oct 1996 22:21:31 +0500 (ESK)
Cc: msmith@atrad.adelaide.edu.au, erich@lodgenet.com, hackers@FreeBSD.ORG
In-Reply-To: <199610261644.RAA28705@labinfo.iet.unipi.it> from "Luigi Rizzo" at Oct 26, 96 05:44:44 pm
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> 
> > Trust me; you can run real-mode '286 code on a V20/V30.  I have done
> > this.  I _believe_ that the Hedley emulator is up to this.
> 
> cannot comment on the first sentence, but for the latter I am sure
> that some intructions are missing. It's been a couple of years
> since I worked on this code, so I have forgotten the details, but
> I remember adding some 286 instructions and some are still missing.
> ENTER/LEAVE are probably two of them, maybe PUSHALL/POPALL as well.
> 
> The fact that some program recognizes the emulated processor as a V20
> does not mean that all V20 instructions are emulated!

These instructions are nearly the whole difference between these
processors (looking from the software point of view). So they
MUST be tested to say which processor it is. 

-SB