Let's Make Robots!

Yet another PWM Picaxe question

I am programming my Mr Basic with Mr Basic moron driver. I use a Picaxe 28x1. It is a very basic setup indeed, with a small servo carrying a sharp IR distance sensor.

After reading many pages of manuals and LMR and example code of other victims, I ran into a wall. It's the dreaded "PWM and servopos don't mix" wall on picaxes.

I understand from all the frustrated posts on LMR that the valid workaround would be to not mix pwm and servo commands. Use one after the other, but never simultaneously. That's were I fail. How do I switch off a servo signal or pwm signal?

My current code makes a PWM signal and the servo responds to it. The electrical signal is not to blame. Noisy as it might be. When I delete the servo commands from my code, but leave everything plugged in (servo, sharp, driver), the servo stops jittering.

I tried to bring the servopin low, to bring the pwm pin low, but neither is stopping the timer issue. Should I force the timer to OFF in between commands? Should my uC take a very short "nap"? Is there an official answer here at all?

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No I had not tried removing the electrical load from the PWM pins yet. That would be a good experiment!

Too bad my experimental board requires a soldering iron to remove those wires. That's probably why I had not thought about it yet.

For future reference (by me mostly): Nuumio confirms: a "low pin" will stop a servopos command on that pin.