ReadMe Raspberry Pi

#Raspberry Pi - Simple This version of working with the Raspberry Pi uses the pi-gpio node.js libraries so gives simple GPIO support for the standard connector.

##Installation

pi-gpio - download, install, configure and test pi-gpio as per the website - https://github.com/rakeshpai/pi-gpio . Note especially the bit about quick2wire's gpio-admin and root access.

Node-RED - as per main INSTALL file, or... in the Pi terminal

cd ~
wget https://github.com/node-red/node-red/archive/master.zip
unzip master.zip
cd node-red-master
npm install
npm install pi-gpio

Then start Node-RED,

cd node-red-master
node red.js

then browse to http://{your-pi-address}:1880

You should see a rpi-gpio input node and output node in the left palette under Advanced.

##Blink

To run a "blink" flow that toggles an LED on Pin 11 on the header, you will need to connect up an LED - as per Gordon's blink sketch. https://projects.drogon.net/raspberry-pi/gpio-examples/tux-crossing/gpio-examples-1-a-single-led/

Import the following flow, by cutting the lines below into your clipboard.

[{"id":"12c3cae6.ed3c35","type":"debug","name":"","active":true,"x":561,"y":119,"wires":[]},{"id":"d4b2ed80.2b4d1","type":"rpi-gpio out","name":"","resistor":"no","pin":"11","x":561,"y":59,"wires":[]},{"id":"5e5e53c0.a1a1ac","type":"inject","name":"tick every 1 sec","topic":"","payload":"","repeat":"1","once":false,"x":121,"y":59,"wires":[["63dad785.9c2528"]]},{"id":"63dad785.9c2528","type":"function","name":"Toggle 0/1 on input","func":"\ncontext.state = context.state || 0;\n\n(context.state == 0) ? context.state = 1 : context.state = 0;\nmsg.payload = context.state;\n\nreturn msg;","outputs":1,"x":321,"y":59,"wires":[["12c3cae6.ed3c35","d4b2ed80.2b4d1"]]}]

Then in the Node-RED browser - Use Options (top right) - Import From - Clipboard, or the shortcut Ctrl-i, and paste in the text, Ctrl-v.

Hit Deploy - and the flow should start running. The LED should start toggling on and off once a second.

##Making Node-RED autostart on boot (optional)

The easiest way to autostart Node-RED is to use screen so you can easily get to the console at any time. To install screen - if not already there.

sudo apt-get install screen

Then edit the etc/rc.local file to include the lines

cd /home/pi/node-red-master
screen -dmS red node red.js

This assumes that you have installed Node-RED to the default (pi) user's home directory.

Once you reboot you should then be able to type

screen -ls

and see red listed. To get to the terminal type

screen -r red

type Ctrl-A-D to detach and leave it running