David
	Hi, I don't want to be rude, ok, but please try to understand this
the right way. I'm just trying to help you here.

	You are trying to design a system and then connect it to the ECU
*before* you know what you really need. This is complicated in 2 ways. First
you will make software and hardware to perform operations that you don't
really need, second, you are not helping the people that is trying to help
you.
	I can understand the concept that you are trying to imply, by doing
everything with the highest standard and then it will certainly work, that
right. But there are other issues to contemplate:

1st. You will be working more than you really need
2nd. your hardware will cost much more than it needs to

So, how would someone proceed?
Well, firs you must characterize de response of the system that you are
controlling. Doing that, will allow you to know how the control signal must
be.

Then, (and only then) when you already know (quantitatively) what you need
to control and how to control it, you can start to think how to generate
such signals.

So, to end this rant, please tell us what the "air counter" does, how is
actually controlled, what is it controlling or whatever information you have
around.

Kind regards,

Mauricio Jancic
Janso Desarrollos - Microchip Consultants Program Member
info@janso.com.ar
www.janso.com.ar
(54) 11 - 4542 - 3519

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