Quote Originally Posted by ronsimpson View Post
My car gives one count per turn of the drive shaft. (output of the transition)
Multiply by the turn ratio of the rear end multiply by the tire circumference.
You just need to count how many pulses per km or mile. Build a counter with a PIC and drive for 1 mile. Every kind of car is different. You need to do the experiment.
Simple project.
Relatively simple project. I have to wonder how 'ugly' that signal will be coming off the sensor, travelling up the wire to the PIC, etc. Might have to square it off a bit with a 7404 or something along those lines so the PIC doesn't get false triggers.