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From: alung@megatest.com (Aaron Lung)
Subject: Re: electronic odometers (was: Used BMW Question ..... ???)
Message-ID: <C5JKCq.K7I@megatest.com>
Organization: Megatest Corporation
References: <1993Apr14.174857.28314@porthos.cc.bellcore.com> <CONRADIE.40.734872761@firga.sun.ac.za> <9833@dirac.physics.purdue.edu>
Date: Thu, 15 Apr 1993 20:22:10 GMT
Lines: 21

In article <9833@dirac.physics.purdue.edu> lovall@bohr.physics.purdue.edu (Daniel L. Lovall) writes:
>
>It shouldn't be THAT hard if you know much about digital electronics.  If the
>counter is made with standard TTL chips, all you should need to do is find
>the chip(s) used for counting, figure out what mileage you want to put in,
>and preset it but wiring the preset pins directly to low/high (you'd also have
>to know what the conventions are for low and high).  It might be a little more
>involved than this, but it shouldn't be beyond someone with a BSEE or BS EET.
>All the display does is convert what the counter chips say into digits using
>a "translation table" stored in ROM.
>

Nobody is using discrete IC's to do these functions anymore if at
all.  I doubt any of the Motor electronics had any to start with.
...Much less TTL.

I can almost guarantee that it'll a fruitless attempt to figure out
how BMW does it without breaking anything and invalidating any
warranty  on the car.  If you're lucky, you'd still be able to
start the car.

