fwd: Info on GM Vehicle Computers

[John S Gwynne]

Please send postings to diy_efi at coulommb.eng.ohio-state.edu. Thanks.


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From: "David Allen" <allent at news1.mnsinc.com>
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Subject:       Info on GM Vehicle Computers
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I am seeking basic information on reading and decoding the single 
line serial output data of the Assembly Line Diagnostic Link (ALDL) in my 
1988 Chevy Van.   Although interestting, I am not as concerned about 
modifying the EPROM or getting at the CPU innards or operation -- I 
just want to know how I can deciper the data stream.   It seems it 
should be a repetitive or cyclic data burst marked by framing bits.  
Any steer or information you could shed on this would be appreciated. 
 I would like to fiddle with decoding the data and perhaps using some 
Visual Basic, providing a windows-based readout, as close as possible 
to real-time.

Many Thanks, 

Dave Allen
WA2BSL
allent at mnsinc.com

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