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A set of input and output nodes for controlling General Purpose Input and Outputs (GPIOs) though the use of johnny-five I/O Plugins as well as running johnny-five scripts!

Install via NPM

From inside your node-red directory:

npm install node-red-contrib-gpio

Control I/O for Analog, Digital, PWM and Servos

input output

Also Read and Write to i2c devices


Node configuration

  • 14 is the length of bytes to read (1 byte = 8 bits)
  • i2c bytes is an array of bytes. You can't use inject node directly because data has to be inside an array.
return msg;
  • i2c read and i2c write configure i2c connection. I2c and register are decimal values! parseInt(x, 10) function is used to read values.

Now with full Johnny-five support!


Supported Hardware

node-red-contrib-gpio supports several johnny-five I/O classes:

Device IO Plugin
Arduino/Firmata firmata
Raspberry Pi raspi-io
BeagleBone Black beaglebone-io
C.H.I.P. chip-io
Galileo/Edison galileo-io
Blend Micro blend-micro-io
LightBlue Bean bean-io
Electirc Imp imp-io
Particle(Spark) Core particle-io

Arduino is supported out of the box, but for other devices, you'll need to install their IO plugin.

For example to install the Raspberry Pi plugin:

npm install raspi-io

Remote Arduino Support

If you're using Arduino/Firmata, you can connect to a remote device via a raw tcp socket, or an MQTT connection.

For example, if you wanted to connect using tcp, in node-red you could specify an ip and port. On another machine with an Arduino plugged in you could run a server that relays a tcp socket to a serial port such as: tcpSerialRelay.js

If you wanted to connect an Arduino to an MQTT server you can use a script such as: bindSerialToMQTT.js. In node-red you can connect to the same MQTT server and subscribe to the topic the arduino is publishing on, while publishing to the topic that the arduino is subscribed to.