docker-nodered-rpi_ws281x

Overview

This project is born from a IoT school work. We needed to connect the Adafruit NeoPixel rings (16 leds and 12 leds) to a Raspberry Py but we haven't anthing exepect the leds and the wires. After seeking on the web I found this tutorial http://frederickvandenbosch.be/?p=1014 which help me a lot. In order to simply a little more the process, I decided to create in Docker container which will contained all the stuff needed in order to be able to make the leds works just with a docker pull and a docker run. Futhermore to make the led utilisation really user friedly and compliant with IoT pusrpose, I wanted to add Node-RED to the container.

Credits

This projet is born thanks to:

• Jeremy Garff rpi_ws281x library (BSD-2-Clause license): https://github.com/jgarff/rpi_ws281x
• Frederick Vandenbosch tutorial: http://frederickvandenbosch.be/?p=1014

What's inside

The docker file is pretty simple, from the official Node-RED image it install the needed package and clone the rpi_ws281x library and initialise the evirnomment. I add some personnal scripts to use basic feature of the leds.

How to build

From Docker hub

$> docker pull johanncoste/rpi_ws281x_nodered:latest

Manually

$> git clone https://github.com/JohannCOSTE/docker-nodered-rpi_ws281x.git .
$> cd docker-nodered-rpi_ws281x
$> docker build -t rpi_ws281x_nodered .

How to run

Beacause of GPIO access, you have to run the container in privileged mode:

docker run -p 1880:1880 --privileged johanncoste/rpi_ws281x_nodered

How to access

It's first a Node-RED container so to access it you have to connect to:

http://0.0.0.0:1880/

Replace 0.0.0.0 by the IP adress of your device

Python scripts and Json flows

Python

There is some default python scripts that will be move inside the container at the root. You case use them directly with Node-RED:

• /color.py r v b blink will light up the led with the r v b color and the led will blink with a frequency of blink second.
• ledtest.py will just display some colors on the leds, you can use it to test if all is correctly wired.

You may have to edit the # LED strip configuration section of them in order to change the number of leds of you device etc.

Json

There is also a Json flow color_flow.json that will show you an exemple of the script usage via Node-RED. You have to import it manually via the Import option in Node-RED.

How to wire

You will find Fritzing file in the fritzing directory (you can download fritzing here).