Raspberry PWM out - a warning

I tried to use the pwm output with an opamp as a source for a 0-10V dimmer. I saw a short spike in the brightness from time to time, 10 - 15 minutes or so.
So i made a simple setup: Slider, a pwm output pin, a 1kOhm resistor and a 2µ2 Elko to ground. I monitored the output with a scope.

The pwm output is not as stable as suggested. For sensitive applications a separate hardware must be used.

The standard node just uses software pwm so it can be affected by other things the pi is doing.
I don't use it myself but the alternative pigpiod node should be more stable as it uses hardware timing

Could somone please share his experience with that node?

Just try it yourself and let us all know if it helps :slight_smile:

I have run 4 servos at the same time using gpiod node - rock solid, vs constant jitter with gpio node with only one servo.

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I tried it now, looks much better!
Now i have 2 quetions:
1 - the requirements for the node point to a line in the rc.local file
The addon is


Is this the same as in Raspi-Configuration, where the GPIO remote access can be activated / deactivated?

2 - The requirements point to a vulnerability in the setup of
/usr/bin/pigpiod -l
The -l option is explained to configure the program for local access only.
I tried this, seeing the node to say connection refused. After removing the -l option it worked. Is there a trick to get that running?

Kind regards

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