5 baud ECM?

[Peter Gargano]

"Malcolm Robb, LC 0112G" wrote:

> I haven't found anyone who knows how it works, or a cheap DIY style PC scan
> tool. Only thing that works is a real Tech1. I'm glad my car is one of the
> few with a P4 in it.

I believe that it's possible to toggle one of the PC's RS232 control lines,
under software control, at about 5 baud, and if it's connected appropriately
to the Tx line (wired OR) then it should work to get the handshake going.
I've seen a JPEG floating around, purportedly from GM, that has a circuit
wired in this manner.

If someone sends me one of these ECMs, I'll see if I can get it working  ;-)

Peter.
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