Hi all,
We are a makerspace that has a K40, and we replaced the controller board on a few years ago which has worked great in Windows. We recently moved it to a Ubuntu machine and had an issue getting Lightburn to see the controller over USB. In Linux, non-root users were unable to access the USB in Lightburn and our license was activated as a shared non-root account. Our resident Linux expert here was able to find the issue and create a udev rule to fix it.
Disclaimer: This worked for us in our situation. We hope that this helps others if they find themselves in a similar situation. Our K40 has a Trocen AWC 708C controller board connected through USB to a custom made desktop PC running Ubuntu 22.04.
This code is added to a new file in the directory /etc/udev/rules.d/ with typically any name, but we used “70-laser.rules” the “.rules” is the important part.
SUBSYSTEM==“usb”, ATTRS{idVendor}==“1fc9”, ATTRS{idProduct}==“0085”, SYMLINK+=“laser-awc708c”, MODE=“0660”, TAG+=“uaccess”
The subsystem idVendor and idProduct define the rules. The symlink creates a name that links the USB to the port where it is plugged in. The mode and tag give access to any logged in users.
In order to get the correct idVendor and idProduct, you can use this script below that prints out the udev info for devices found in /dev. We ran this script, searched for Trocen in our case, and copied the vendor and product numbers from those results.
#!/bin/bash
for devpath in $(find /dev/ -type b,c,p,s); do
echo “DEVICE $devpath”
udevadm info -q all “$devpath”
echo “”
echo “”
done
I do hope that this helps others, as we didn’t find any solution online when we were working through this before, and know that someone else down the road will be in a similar situation.