Manjaro / Arch linux : Error opening connection: Could not connect to controller on port jserialcomm://ttyUSB0

[SvenMeyer]

Version

Other - Universal Gcode Platform 20240709

Hardware / Firmware

GRBL 1.1

What happened

Product Version: Universal Gcode Platform 20240709
Java: 13.0.1; OpenJDK 64-Bit Server VM 13.0.1+9
Runtime: OpenJDK Runtime Environment 13.0.1+9
System: Linux version 6.9.5-1-MANJARO running on amd64; UTF-8; en_US (ugsplatform)
User directory: /home/sum/.ugsplatform
Cache directory: /home/sum/.cache/ugsplatform/var/cache

I installed candle2-git (V2.4.r34.2ad3200.59.d41d8cd) from the AUR just using the built in software manager. (as far as I remember I added myself sum as a user to the user group tty) ... and Candle2 has no problem to connect to my CNC 3018.

I also installed UGS from the AUR just using the built in software manager, but every time I click the connect button I get the error:
Error opening connection: Could not connect to controller on port jserialcomm://ttyUSB0

I also added myself to the group uucp, logged out and back again to be sure, checked the groups

$ groups sum
wheel lp tty uucp sys network power autologin sum

$ ls -l /dev/ttyUSB0
crw-rw---- 1 root uucp 188, 0 Jul 10 21:58 /dev/ttyUSB0

... however, no change, same error :-(

How to reproduce

See above ...

Operating System

Linux version 6.9.5-1-MANJARO amd64

Anything else

log file : messages.log

[SvenMeyer]

[UPDATE] I just found this old post
https://bbs.archlinux.org/viewtopic.php?id=178552
which suggests to do (each time) also
sudo chown $USER /dev/ttyUSB0

Now I was able to connect and got some messages in the console window

*** Connecting to jserialcomm://ttyUSB0:115200
>>> ?
ok
>>> $I
[VER:]
[OPT:V,15,511]
ok
>>> $$
$0 = 8    (Step pulse time, microseconds)

... <snip> ...

$132 = 200.000    (Z-axis maximum travel, millimeters)
ok
>>> $G
[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]
ok

However, UGS disconnects right thereafter.

Now when I click the connect button I can not reconnect and get the initial error message again.

If I restart UGS, I can again connect only once as above ...

[breiler]

Sorry for the late reply.

I think that you've been on the right track adding the right user roles. The group that you added to your user should have sufficed but it might needed a complete restart?

The workaround that you did with sudo chown $USER /dev/ttyUSB0 does basically the same thing but will not be persisted between restarts.

The response [VER:] from the controller tells me that this isn't a "original" GRBL and that the firmware has been modified by the vendor. We use this response to figure out what firmware version this is. Since the vendor has removed it we will assume that it is GRBL 1.1. Are you certain that it is GRBL 1.1 compatible and not GRBL 0.9?

Can you post your messages.log after you tried to connect and it got disconnected and the complete console log messages with verbose enabled (right click in the console and click "Enable verbose logging")?

[breiler]

Closing as we didn't receive further updates from the user