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From: jerry@starfish.Convergent.COM (Gerald Hawkins)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Looking for AT Bus Technical Reference.
Message-ID: <811@starfish.Convergent.COM>
Date: 16 Nov 88 00:23:34 GMT
References: <4254@tekgvs.GVS.TEK.COM>
Organization: Convergent Technologies, San Jose, CA
Lines: 36

From article <4254@tekgvs.GVS.TEK.COM>, by keithe@tekgvs.GVS.TEK.COM (Keith Ericson):
> In article <5887@fluke.COM> witters@tc.fluke.COM (John Witters) writes:
>>I'm going to be designing a peripheral for the IBM AT bus.  I'd like to find a
>>good technical reference for the AT bus.
>>					   I'd really like to have something
>>which describes both the "official" bus, as well as "ill behaved", but popular
>>versions of the bus.  The reference should include detailed timing
>>specifications and bus protocols.
-
-
I mailed this earlier directly to the poster.  Someone can correct me if
I am wrong ... There is NO SUCH DOCUMENTATION.  There is NO OFFICIAL BUS.
It is likely that IBM created the bus without ever producing timing
specs.  Convergent created the first 8086 based individual workstation
slightly before IBM did the PC, and we also created no proper bus
documentation--a situation that IBM never remedied (but Convergent did).
I guess there is an advantage to being small.

So, when you design a peripheral for IBM, be forewarned that IBM won't
even accept that such a thing might work with their machines; and if it
works with a real IBM, it may not work with all compatibles.  The only
way to tell is to test with a representative sample.  So they tell me in
our design group.  As the designer of a PC-AT compatible, you get the
chore of testing the product with every major (and many minor) software
packages, plus most of the major add-in cards.

Good Luck!


Rainy Days and
Automatic Weapons Fire
Alway Get Me Down.

These opinions are mine.
Jerry.  (jerry@starfish.convergent.COM)
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