Interfacing Arduino With Node-RED

Introduction

Node-RED is a tool for wiring together hardware devices, APIs and online services in new and interesting ways.

Node-RED provides a browser-based flow editor that makes it easy to wire together flows using the wide range nodes in the palette. Flows can be then deployed to the runtime in a single-click.

• NodeRED Homepage

• Installation guide

Why Node-RED?

• Open-source

• Multi-platform/Cross-platform

• Browser based and supported by cloud platforms like Bluemix of IBM.

• Visual programming tool

• Supports real-time automation of M2M and IoT protocols.

• Future of Industrial IoT(Internet of Things)

STEP 1

Preparing your Arduino Uno board:

Im working with- Arduino UNO and MQ-7 gas sensor, you can use any analog sensors of your choice, even a POT would do.

Things to follow:

• Baud-rate should be 57600.

• Delay should be more than 60000 ms, as per Twitter standards.

• Don't use/open your serial monitor, keep your COM port free.

• Keep your arduino board connected to your computer.

Code

const int AOUTpin= 0; 
int value;  
void setup()   
{ 
Serial.begin(57600);
pinMode(AOUTpin, INPUT);
}  
void loop() 
{ 
value= analogRead(AOUTpin);
Serial.print("CO value: "); 
Serial.println(value);
delay(60000); 
} 

STEP 2

• Download node.js for your computer, Click here.

• Open the command prompt and install Node-RED with these commands:

 npm install -g node-red 

• Now run your Node-RED, with this command:

 node-red 

• Copy the local-server link to your browser (Chrome) http://localhost:1880/#

STEP 3

Explore Node-RED

Panels of Node-RED:

• Nodes Panel, list of nodes.(Left-end)

• Flow Panel, to design your flow/wiring of the project.(Middle)

• Third one is of three sub panels named as INFO panel, Debug panel and Dashboard panel.(Right-end)

• Explore them.

STEP 4:

Now it is time to create your project:

Choose the following NODES:

• Serial Node Input

• Twitter Node

• Text Node from Dashboard and

• debug node.

(or)

Copy and Import the following code (Menu>Import>Clipboard):

 [{"id":"d6230d5f.c05e","type":"serial in","z":"b9075383.db257","name":"","serial":"1b8769a6.621dc6","x":91,"y":135,"wires":[["ea730c90.ebc4b","84c15113.4ecec","e146cbcf.251818"]]},{"id":"ea730c90.ebc4b","type":"debug","z":"b9075383.db257","name":"","active":true,"console":"false","complete":"false","x":501,"y":274,"wires":[]},{"id":"e146cbcf.251818","type":"twitter out","z":"b9075383.db257","twitter":"","name":"Tweet","x":689,"y":144,"wires":[]},{"id":"84c15113.4ecec","type":"ui_text","z":"b9075383.db257","group":"90f1c978.bba628","order":0,"width":0,"height":0,"name":"CO in PPM","label":"Arduino Reading","format":"{{msg.payload}}","layout":"col-center","x":467,"y":41,"wires":[]},{"id":"1b8769a6.621dc6","type":"serial-port","z":"b9075383.db257","serialport":"COM7","serialbaud":"57600","databits":"8","parity":"none","stopbits":"1","newline":"\\n","bin":"false","out":"char","addchar":false},{"id":"90f1c978.bba628","type":"ui_group","z":"b9075383.db257","name":"CarbonMonoxide in Atmosphere","tab":"93b83a33.771108","disp":true,"width":"9"},{"id":"93b83a33.771108","type":"ui_tab","z":"b9075383.db257","name":"Home","icon":"dashboard"}]  

You should modify the Nodes, with your custom settings.

And click DEPLOY BUTTON to run your program.

STEP 5