No connection to Lightburn after upgrading to Ubuntu 22.04

[peter.s (Peter Smith)]

I have been using Lightburn 1.1 under Ubuntu 21.10 with no troubles on an Asus Core I7 laptop.
I then upgraded Ubuntu to 22.04 and found that Lightburn could not connect to my Sculpfun S9 laser.
I performed an lsusb command and found the"1a86:7523 QinHeng Electronics CH340 serial converter(found in my Sculpfun) was recognised by Ubuntu. I then performed a dmesg command and found that the CHG340 serial converter had been linked to my Webcam, making it unavailable to Lightburn.

Then I issued the command grep -riIn “1a86:7523” /usr/lib/udev/rules.d/*
and this returned the result
/usr/lib/udev/rules.d/85-brltty.rules:330:# Device: 1A86:7523

Ah, that was what was wrong. My 1A86:7523 CHG340 had been claimed as a Braille device.
I commented out the offending line,
ENV{PRODUCT}==“1a86/7523/*”, ENV{BRLTTY_BRAILLE_DRIVER}=“bm”, GOTO=“brltty_usb_run”

But I still wasn’t out of the woods. I still could not access the laser.
Next I added the following line to /usr/lib/udev/rules.d/70-uaccess.rules
SUBSYSTEM==“tty”, ATTRS{idVendor}==“1a86”, ATTRS{idProduct}==“7523”, GROUP=“users”, MODE=“0666”
after
3D printers, CNC machines, laser cutters, 3D scanners, etc.

I restarted the machine and success. Lightburn can access my Sculpfun S9 from Ubuntu 22.04

I hope this information can be useful to any other Ubuntu user who cannot access his laser after upgrading Ubuntu.

[jkwilborn (Jack Wilborn)]

Probably needed to reload udev rules…

Should stop communications, reload ‘rules’ and the triggers and restart communications… I usually get away with just

udevadm control --reload-rules
udevadm trigger

It should avoid a re-boot.

[peter.s (Peter Smith)]

Good point

[jkwilborn (Jack Wilborn)]

Anytime you modify the source data to a system ‘part’ you need to ‘roll it over’ so it restarts and re-reads the data. You have to play the same game with DHCP and other system ‘things’…

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Funny, when I first went to work in computers, I fixed terminals. It was rather surprising to go to someone cubical at night and find they have a braille terminal…

Couldn’t fix it without their help…

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Take care