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From: mslater@cup.portal.com (Michael Z Slater)
Newsgroups: comp.sys.intel
Subject: Re: LOADALL for 80286 & 80386
Message-ID: <19820@cup.portal.com>
Date: 23 Jun 89 19:01:45 GMT
References: <31249@conexch.UUCP> <233@guardian.UUCP>
Organization: The Portal System (TM)
Lines: 22

>Seriously, assuming info on the alleged instruction wasn't freely available,
>what's the big deal?  From what I've heard, the instruction was intended for
>the testing of the component and was never intended for general use.  So
>someone figured out it exists, or some large customer wanted to do their own
>in-coming testing and the info leaked out.  How does that put an obligation
>on Intel to provide that info to anyone who asks?

The instruction was designed for testing, but because of the limitations of
the 286 architecture, it turned out to be genuinely useful for operating
system code and certain utilities, such as ram disks and ems emulators.
Microsoft uses it in their RAMdrive program and in OS/2, and I've been told
that it is used in some ROM bios code and in several ems emulators.  Thus,
if I am a vendor of RAM emulators and haven't been given this info, then I
can't compete with Microsoft on a fair basis.

I understand Intel's concern that they don't want to make something a part
of the architecture that they don't intend to support in future products.
The solution to this is simple; the documentation just states that this
is an implementation-specific function, is not part of the architecture, and
should be used with great care and only after testing for processor type.

Michael Slater, Microprocessor Report