> If anyone is interested, I have found a good example of the physical
> interface from a OBD to a PC using a mcu:
> http://www.elmelectronics.com/DSheets/ELM320DS.pdf
>
> Nothing big really, but a handy circuit none-the-less.
>
> I think the product on that site is a little PIC12C508 or something
> pre-programmed.  I might buy one just to save the hassle of writing my own
> code.

You can save even more time by buying the whole circuit:

http://www.scantool.net/products/elmscan_pwm.htm  :-)

Open source software is also available:

http://www.scantool.net/software/software.htm

Regards,

Vitaliy

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