Roadrunner technical documentation

Install and run Node-RED on RoadRunner

This article illustrates how to install Node-RED version 1.2.6 on the Roadrunner SOM

Node-RED is a programming tool for wiring together hardware devices, APIs and online services in new and interesting ways.

It provides a browser-based editor that makes it easy to wire together flows using the wide range of nodes in the palette that can be deployed to its runtime in a single-click.

Installing Node-RED on Roadrunner SOM

The Node-RED comunity provides a script to install Node.js, npm and Node-RED onto Debian or Raspberry Pi OS.

This script can be used also for the RoadRunner. The script can also be used to upgrade an existing install when a new release is available.

Running the following command will download and run the script:

bash <(curl -sL https://raw.githubusercontent.com/node-red/linux-installers/master/deb/update-nodejs-and-nodered)

Running as a service

The install script for the Pi also sets it up to run as a service. This means it can run in the background and be enabled to automatically start on boot.

The following commands are provided to work with the service:

  • node-red-start - this starts the Node-RED service and displays its log output. Pressing Ctrl-C or closing the window does not stop the service; it keeps running in the background
  • node-red-stop - this stops the Node-RED service
  • node-red-restart - this stops and restarts the Node-RED service
  • node-red-log - this displays the log output of the service

Autostart on boot

If you want Node-RED to run when the Pi is turned on, or re-booted, you can enable the service to autostart by running the command:

sudo systemctl enable nodered.service

To disable the service, run the command:

sudo systemctl disable nodered.service

Open the Node-RED developer interface

Once Node-RED is running you can access the editor in a browser: http://roadrunner_ip_address:1880

Refer to the rich set of tutorial available on Node-RED website to learn how to use it

Using the GPIO lines using the node node-red-contrib-roadrunner

Node-red-contrib-roadrunner is a node developed by Antonio Galea to set and get the Roadrunner GPIO lines state in Node-RED

To install this node type this commands:

sudo apt update
sudo apt install python3-libgpiod
cd ~/.node-red/
npm install node-red-contrib-roadrunner

If you are running Node-RED as a normal user, be sure to give the necessary permissions to /dev/gpio0. One simple way is to save this text:

KERNEL=="gpiochip0", MODE="0666"

inside a file called:

/etc/udev/rules.d/60-gpiochip.rules

Then restart Node-RED:

sudo systemctl restart nodered.service

or

node-red-restart

Links

Sergio Tanzilli
Systems designer, webmaster of www.acmesystems.it and founder of Acme Systems srl

Personal email: tanzilli@acmesystems.it
Web pages: https://www.acmesystems.it --- https://www.acmestudio.it
Github repositories: https://github.com/tanzilli --- https://github.com/acmesystems
Telegram group dedicated to the Acme Systems boards: https://t.me/acmesystemssrl

Roadrunner technical documentation