Node.js
Communication Arduino avec nodeJs

Introduction

Node Js communication avec Arduino via serialport

Node js code

Un exemple pour démarrer cette rubrique est le serveur Node.js communiquant avec Arduino via serialport.

npm install express --save
npm install serialport --save

Exemple d'application.js:

const express = require('express');
const app = express();
var SerialPort = require("serialport");

var port = 3000;

var arduinoCOMPort = "COM3";

var arduinoSerialPort = new SerialPort(arduinoCOMPort, {  
 baudrate: 9600
});

arduinoSerialPort.on('open',function() {
  console.log('Serial Port ' + arduinoCOMPort + ' is opened.');
});

app.get('/', function (req, res) {

    return res.send('Working');
 
})

app.get('/:action', function (req, res) {
    
   var action = req.params.action || req.param('action');
    
    if(action == 'led'){
        arduinoSerialPort.write("w");
        return res.send('Led light is on!');
    } 
    if(action == 'off') {
        arduinoSerialPort.write("t");
        return res.send("Led light is off!");
    }
    
    return res.send('Action: ' + action);
 
});

app.listen(port, function () {
  console.log('Example app listening on port http://0.0.0.0:' + port + '!');
});

Exemple de serveur express:

node app.js

Code Arduino

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.

  Serial.begin(9600); // Begen listening on port 9600 for serial
  
  pinMode(LED_BUILTIN, OUTPUT);

  digitalWrite(LED_BUILTIN, LOW);
}

// the loop function runs over and over again forever
void loop() {

   if(Serial.available() > 0) // Read from serial port
    {
      char ReaderFromNode; // Store current character
      ReaderFromNode = (char) Serial.read();
      convertToState(ReaderFromNode); // Convert character to state  
    }
  delay(1000); 
}

void convertToState(char chr) {
  if(chr=='o'){
    digitalWrite(LED_BUILTIN, HIGH);
    delay(100); 
  }
  if(chr=='f'){
    digitalWrite(LED_BUILTIN, LOW);
    delay(100); 
  }
}

Démarrage

1. Connectez l'arduino à votre machine.
2. Démarrer le serveur

Contrôler la construction en led via le serveur js noeud express.

Allumer la led:

http://0.0.0.0:3000/led

Pour éteindre la led:

http://0.0.0.0:3000/off