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From: greg@gryphon.CTS.COM (Greg Laskin)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Switching from Protected to Real Mode
Message-ID: <1343@gryphon.CTS.COM>
Date: Wed, 26-Aug-87 19:20:19 EDT
Article-I.D.: gryphon.1343
Posted: Wed Aug 26 19:20:19 1987
Date-Received: Sat, 29-Aug-87 06:00:55 EDT
References: <1387@imagen.UUCP> <4047@utai.UUCP>
Reply-To: greg@gryphon.CTS.COM (Greg Laskin)
Organization: Trailing Edge Technology, Redondo Beach, CA
Lines: 30
Keywords: 286

In article <4047@utai.UUCP> anton@ai.UUCP (Anton Geshelin) writes:
>There is an undocumented instruction in the 286 which will throw you back
>into the unprotected mode.  Microsoft has found it so useful that they
>insist that Intel not fix it in the 386.  At least, these are the
>rumors I heard.

I saw a real posting in comp.sys.intel a few months ago that made obscure
reference to such an instruction, LOADALL or thereabouts.

The poster, perportedly an Intel person speaking on his own, stated:
   1)  The documentation for this undocumented instruction was made
	made available to Intel largest customers (IBM and Microsoft)
	under non-disclosure agreements.
    
   2)  The instruction, present in the 80286, was incompatible with the
	80386.

   3)  The instruction was documented for the customers who got the
       documentation because of their "special needs" but that Intel
       would not support the instruction and strongly recommended
       against its use, in large part because of the 80386 incomptability.

All information provided herein supplied with a dose of salt.

-- 
Greg Laskin   
"When everybody's talking and nobody's listening, how can we decide?"
INTERNET:     greg@gryphon.CTS.COM
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