The project detour number...I lost count...is progressing quite nicely. The goal is to line up the edges. Instead of the brain-dead-simple (too high? -1 too low? +1) logic, I need to write a PID controller (or something like it) to avoid this sort of amusing to watch hunting. #electronics
@jeffpc That looks like you have some delay somewhere in your control loop? Otherwise a simple bang bang control shouldn't produce overshoot like that, just an oscillation by +/-1 that can be removed with some hysteresis.
@jaseg The uC controls a DAC which sets the OCXO's tune pin voltage. There is definitely a delay (1s) between updates, but I think the problem is that I do the +/-1 every time the phase difference is +/-. So, if it takes 5 iterations for the phase diff to change signs, I'll end up with +5/-5 depending on the direction. Which is generally too much.
Today I intend to implement a PID controller...or something approximating one. Even just a P-controller would be a step up.
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