>i've got an automotive project based on a 16f877 that works fine in 99% of
>applications, but when i
>get it in a car with a magneto ignition, my PIC is freaking out .. resets /
>locks / jumps to random
>locations in code.

The dreaded noise problem.  I have this EXACT same problem with a radio
control project that just uses servos.  The funny part about the whole thing
is that it works fine if the supply voltage stays above 5.10V, but when it
drops below that, beware of random resets when the servos are actuated.
It's strange stuff. I've noticed that it's worse with microcontrollers that
have a Brown-out reset feature (enabled or not, doesn't matter).  For chips
that don't have that internal circuitry, I have no problems.

Most people will probably suggest some caps to filter out the noise, but I
have tried this in some applications without success.  But I'd LOVE to hear
more suggestions for how to prevent this, and I'd be glad to try them all
until one works.

--Andrew

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