Pi Lite with Node-RED
This was trivially easy, but it’s a nice example of how simple integration is now becoming due to the strength of various open source communities.
The Pi Lite is an array of lots of LEDs (126 in a 9×14 matrix to be exact). I bought a pair of them during the initial Kickstarter campaign. It has its own micro controller, and is accessed via a serial port, which means it’s pretty easy to get messages onto it from most languages and frameworks.
Node-RED is a visual integration tool that runs on node.js. It’s very easy to get it going on a Pi using Raspbian:
# First install node.js wget http://node-arm.herokuapp.com/node_latest_armhf.deb sudo dpkg -i node_latest_armhf.deb # Make sure we have git sudo apt-get install -y git-core # Install Node-RED git clone https://github.com/node-red/node-red.git cd node-red npm install --production # Install serialport package npm install serialport #Start Node-RED node red.js
Once up and running browse to http://pi_ip:1880 and wire together a ‘Hello World’ example with an inject input (with a Paylod of ‘Hello World’) and a serial output (configured for /dev/ttyAMA0 at 9600 baud):
Now clicking on the button on the Hello World injector results in Hello World scrolling across the Pi Lite in large friendly letters :)
Once that’s running then it’s easy to substitute messages coming from tweets, MQTT queues or whatever else and feed them onto the matrix.
 Since the GPIO serial port is normally set up for logging and console access it’s necessary to do some reconfiguration before using the Pi Lite.
Filed under: Raspberry Pi | 1 Comment
Tags: node, Node-RED, node.js, PI, Pi-Lite, Raspberry Pi, raspbian, RPi, serial, serialport, ttyAMA0