1226870 ecm questions

[Ludis Langens]

Mike <Mikepoore at aol.com> wrote:
> I am trying to link my laptop to the ecm datastream. I have learned that it 
> is 160bps and that a 10k resistor between the A and B terminals will put the 
> ecm into diagnostics mode.

Check the archives.  Your question is a Frequently Asked Question.

> 1. What are the communications parameters, i.e. data bits, stop bits, parity, 
> etc.
> 
> 3. 160 bps is not a com port option on the menu. Can I just type it in and it 
> work?

Variable pulse width / duty cycle bit encoding, one start bit (sort of),
8 data bits, no stop bits, no parity.  Your serial port is not capable
of these settings.

If you look through the archives, I suggested a method that might allow
your standard serial port UART to receive ALDL data.  It involves
setting the data rate to something in the 2000 baud to 3000 baud range. 
You will receive one _byte_ for each ALDL _bit_.  You then get to
extract the data stream from these bytes via software.

> If anyone can answer the following questions, I would greatly appreciate it:

Check this out:
  http://www.isthq.com/~dan/aldl.htm

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/