ALDL project

[steve ravet]

Will Honea wrote:
> 
> I just snagged this group and spent the time to scan the archives on this topic - just what I needed, since
> I was in the process of 're-inventing the wheel', as it were.  As the project has progressed as far as it
> has, the following document may provide some info for future reference as it (inevitably) progresses into
> OBDII.  All the communications protocols are explained in detail - frames, formats, etc.  No specific codes,
> but at least it defines the data formats!
> 
> ftp://download.intel.com/design/intarch/papers/J1850_WP.PDF
>   - or -
> http://134.134.214.34/design/intarch/papers/j1850_wp.pdf
> 
> Now, if I can just paste enough of this together to figure out what the !@#$%^ is going on with my wife's
> Cadillac Cimmaron, I might be able to contribute a bit - MSEE, 25 years experience in data aquisition and
> analysis, I have access to PCB facilities if it ever gets that far.
> 
> Will

Hi Will, I think you might be on the wrong track.  SAEJ1850 is OBD-II
which has only come around in the last couple years.  Previously all
manufacturers invented their own methods of communicating with ECMs. 
GMs diagnostic link was called ALDL, and came in two major flavors as
noted in the archives, 160 baud and 8192 baud.  Your wife's Cimmaron is
ALDL, not OBD-II.  Sorry...

--steve


--
Steve Ravet
International Meta Systems
http://www.imes.com
steve at imes.com