Universal Robots Forum

Digital Output as PWM


as the title says, we want to make a PWM like signal on one of the digital outputs and we are not sure that is possible or even a good idea.
We didn’t find an embedded soultion for this, so we tought, we can use one of the Digital Output pin.

I have read that the maximum scan time for an I/O is 4ms in the e-series, so that could mean, we can make a maxium 125Hz signal with 50% pulse width?
If we run this fast DIO ON - DIO OFF in a separete thread, could be there any problem?
How deterministic the signal would be? There could be random pulse widths or every pulse will be the same?
Is it okay for the Control Box, or is it a bad practice?
Or just forget all this, and connect the robot to a microcontroller and that should do the work?

Thank you for your answers!

We hit the same issue previously to fade an LED lamp and for sake of simplicity got a small ATTiny mcu reading one of the 0-10V analog output through a voltage divider showing 0-5V, then outputting a PWM signal for control. Would have indeed be easier directly on board but then you have a 24V pwm output, so if you need to level shift this anyway much easier than bit-banging an IO.

Just buy a cheap plc with, modbus tcp network connection and pwm outputs. Then you can start pwm’s from you UR modbus tcp server. Its like 300 EUR

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