The SKR V1.3 is connected to the small adapter board for the ribbon cable. Today I wanted to do the first test. Now it’s about the connection of the SKR with the laser PSU. In the meantime I have read a lot about how the board should be connected to the PSU in many forums and also here.
To be on the safe side, I also looked up the Smoothiewaredoku again and found that:
In order to control the power of the laser tube, the laser PSU reads a PWM signal as it’s input.
Please look at the datasheet for your PSU to know which connection that signal is wired to.
From the Smoothieboard, you need to connect :
One GND pin to the Ground connection on the PSU
One of Smoothie’s PWM pins to the PWM input on the PSU”
So they only connect one cable, namely the PWM signal with the PSU!
The PSU has two inputs:
L = switches the laser on and off
In = controls the power of the laser
If the PWM is clamped from the board to the In of the PSU, L would have to be constantly set to 0 (laser is always on) so that the power could be controlled from 0 to 100% and thus also activated or deactivated.
If the PWM from the board is clamped to the L of the PSU, the laser power must be set to a fixed value with a potentiometer connected to in, so you can no longer change the power via the software, right?
Or is it meant that with the PWM from the board you can switch the L from the PSU on and off so quickly that the power can then be changed?
I believe this is the most frequently asked and discussed question when upgrading!