Ubuntu and cncjs AutoLevel

There are several ways to install cncjs:

• source code
• Electron app
• Docker

AutoLevel is currently not part of official cncjs, therefore the only way to get AutoLevel is to run from source code. In this instance, we will use Ubuntu 22.04 as the operating system.
We will install cncjs with the AutoLevel modification from the source code, build the project, and run the app.

Open a terminal in Ubuntu.

Install node version manager nvm

The current AutoLevel widget is based on cncjs version 1.10.3. cncjs 1.10.3 will not run with the latest node version, but it will run with node version 14.
The node version manager nvm allows to choose the node version.

log out and back in so that .bash_rc is run

List available versions:

Install node

Install node version 14 by

Switch node version

Every time we open the terminal, we have to make sure that we are using node version 14.
There are ways to make this switch permanent, but I have tried and they didn't work, leading to errors that were hard to trace.
The saftest way to ensure the correct node version is to run this every time you open the terminal:

Install yarn

yarn is the package manager used to manage this project.
Install yarn:

Retrieve the source code

Clone the cncjs repository with the AutoLevel modification to your local computer
and switch to the folder in which cncjs_1_10_3_AL is installed.

Initial project install

Run to install the dependencies, then run to build the app.

Start the cncjs server

Run You should see something similar to this:

Hold the CTRL-key on the keyboard and mouse-click on the link
http://127.0.1.1:8000/
You should see a browser opening, displaying the workspace of cncjs

Arduino Serial Port Permission

The GRBL software runs on an Arduino, for example an Arduino Mega. When the Arduino Mega is connected, the port appears in the Connection widget as /dev/ttyACM0.

However, an error message may appear:
"Error opening serial port"

https://www.arduino.cc/en/Guide/Linux#toc6

To resolve:
Test current permissons:
gives
so root is owner.

Solution: add our user to the group:

To put the change into effect:

logging out and back in should theoretically work,
but in my case, only rebooting worked.