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Old 01-30-2010, 01:43 AM   #2908 (permalink)
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Originally Posted by adamj12b View Post
The only problem I have about integrating with the vehicle speed sensor is every make can be different.
You are preaching to the choir here But it would make a nice optional feature for those who want that sort of functionality (mileage/speed performance tracking, anti spin, anti-lock,cruise,easy on your synchros shifting) and are willing to sort it.

Originally Posted by adamj12b View Post
Detecting wheel spin could still be done with just a tach sensor on the motor as the VSS will be inside the transmission which is close enough to the motor to work the same.
Not quite. If like most FWD cars you have the speed sensor tied to one wheel, then that is how you detect when a wheel is spinning. The motor rpm picks up but either the wheel is spinning too fast for the motor rpm or it is too slow, and the rpm to speedo ratio does not match any known ratios. Regen braking is the same way, but that is another issue, for another controller.

Originally Posted by adamj12b View Post
Rev matching could be a cool feature. I will have to think of this more. The only problem comes back to interfacing to the VSS. The other thing that im not a huge fan of is connecting to the VSS is more intense of an install. You will have to locate the wire that is the VSS, and tie onto it and go back into the controller.
yup, we wrestle with vss a lot with the mpguino. Instant and average Distance/speed is such a useful metric in things transportation though that it is worth some wrestling:
MPGuino - EcoModder and a bit of wire cost a lot less than a gps module and is far more precise on instantaneous values (good enough to shift by I recon).

Originally Posted by adamj12b View Post
The cruise control system I came up with would keep circuitry, wiring and installation very simple.
It looks like plenty of adc and interrupt pins are still open, what I will probably wind up doing is using a resistor network on an adc if spare pins are tight, to put several buttons on one pin. Personally I would rather look up a button function on a range of values than do "signal processing" on it.

And again the speed signal could tell you if they put the clutch in or slipped into neutral if you know the ratios (could also train the ratios with some interface).

I'm just thinking out loud here, nice to have for the most part.
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