Flywheel/Encoder patterns

[Walters Chris]

>This is exactly what I was thinking about when I decided to use 180
>teeth.  I figured if I use a lower resolution, I would have to calculate
>RPM (which I have to do anyway), then calculate time elapsed per degree
>of rotation (which is estimated), and load my counter.  By going to 180
>teeth, I've eliminated the last two steps, and all events happen once
>per degree based on an actual signal, not an estimated value.  I realize
>that this approach also generates more interrupts per revolution, but it
>seems easier to work with.

I thought 60 was the practical limit on number of teeth on a timing gear - 
above that and you'd start to lose resolution.

Rather than counting pulses, has anybody thought about encoding the timing 
gear such that you can read crank position directly off the gear? Sortof 
like a shaft encoder.

Snake
no cool Fords yet, one cool Dodge