Communication between Raspberry Pi and Arduino, using Node.js

The 'serialport' module for Node.js provide basic building block to make Node.js communication with serial port. Here is a simple example to send data between Raspberry Pi and Arduino Esplora board via USB, using Node.js.

Cross-post with Arduino-er: Arduino + Raspberry Pi + Node.js



node_arduino.js, Node.js script run on Raspberry Pi side.

//To install 'serialport' locally, enter the command:
//$ npm install serialport
//Otherwise, Error: Cannot find module 'serialport' will reported

var SerialPort = require("serialport").SerialPort
var serialPort = new SerialPort('/dev/ttyACM0', 
    {   baudrate: 9600,
        dataBits: 8,
        parity: 'none',
        stopBits: 1,
        flowControl: false
    });

serialPort.on("open", function () {
    console.log('open');
    serialPort.on('data', function(data) {
        console.log('data received: ' + data);
        });
    serialPort.write("Hello from Raspberry Pi\n", function(err, results) {
        console.log('err ' + err);
        console.log('results ' + results);
        });
});

The code in Arduino Esplora board.

#include <Esplora.h>
#include <TFT.h>
#include <SPI.h>
 
int prevSw1 = HIGH;
int incomingByte = 0;
String charsIn = "";
char printout[20];  //max char to print: 20
  
void setup() {
   
    EsploraTFT.begin();  
    EsploraTFT.background(0,0,0);
    EsploraTFT.stroke(255,255,255);  //preset stroke color
      
    //Setup Serial Port with baud rate of 9600
    Serial.begin(9600);
     
    //indicate start
    Esplora.writeRGB(255, 255, 255);
    delay(250);
    Esplora.writeRGB(0, 0, 0);
     
}
  
void loop() {
    int sw1 = Esplora.readButton(SWITCH_1);
    if(sw1 != prevSw1){
      if(sw1 == LOW){
        Serial.println("Hello from Arduino Esplora");
      }
      prevSw1 = sw1;
    }
     
    while (Serial.available()) {
      char charRead = Serial.read();
      charsIn.concat(charRead);
    }
    if(charsIn != ""){
      Serial.println("How are you, " + charsIn);
      charsIn.toCharArray(printout, 21);
      EsploraTFT.background(0,0,0);
      EsploraTFT.text(printout, 0, 10);
      charsIn = "";
    }
}