node-red-nodes/hardware/Arduino

node-red-node-arduino

A Node-RED node to talk to an Arduino running firmata.

Note : This is the same node as is/was in the core of Node-RED. If you already have it installed you do NOT need this node. However it will be deprecated from the core in due course, at which point you will need to install it from here if still required.

Install

Run the following command in the root directory of your Node-RED install, usually this is ~/.node-red .

    npm install node-red-node-arduino

Usage

The Firmata firmware must be loaded into the Arduino.

See the main documentation for details and examples of how to use this node.

###Input Node

Connects to local Arduino and monitors the selected pin for changes.

You can select either Digital or Analogue input. Outputs the value read as msg.payload and the pin number as msg.topic.

It only outputs on a change of value - fine for digital inputs, but you can get a lot of data from analogue pins which you must then handle.

You can set the sample rate in ms from 20 to 65535.

###Output Node

Connects to local Arduino and writes to the selected pin.

You can select Digital, Analogue (PWM) or Servo type outputs. Expects a numeric value in msg.payload. The pin number is set in the properties panel.

###Example

Simple flow to blink Pin 13

    [{"id":"d7663aaf.47194","type":"arduino-board","device":""},{"id":"dae8234f.2517e","type":"inject","name":"0.5s tick","topic":"","payload":"","payloadType":"date","repeat":"0.5","crontab":"","once":false,"x":150,"y":100,"z":"359a4b52.ca65b4","wires":[["56a6f8f2.a95908"]]},{"id":"2db61802.d249e8","type":"arduino out","name":"","pin":"13","state":"OUTPUT","arduino":"d7663aaf.47194","x":570.5,"y":100,"z":"359a4b52.ca65b4","wires":[]},{"id":"56a6f8f2.a95908","type":"function","name":"Toggle output on input","func":"\n// If it does exist make it the inverse of what it was or else initialise it to false\n// (context variables persist between calls to the function)\ncontext.level = !context.level || false;\n\n// set the payload to the level and return\nmsg.payload = context.level;\nreturn msg;","outputs":1,"noerr":0,"x":358,"y":100,"z":"359a4b52.ca65b4","wires":[["2db61802.d249e8"]]}]