Send string command from Android to Arduino in USB Host Mode

This is a example in my another blog show how Android send command to Arduino in USB Host mode. When user toggle the LED by clicking on the button, or change the screen color by slideing the bars, the commands will be add in a command queue, and then send to Arduino in background.

The code in Arduino Esplora is same as the previous example of Node.js + Arduino, running on PC.

Arduino Day with Massimo Banzi - ASK AN ENGINEER LIVE SHOW at 7pm ET

Celebrate Arduino Day 2014 with Massimo Banzi, the co-founder and CEO of Arduino and Adafruit on a special Saturday night 7pm ET March 29th, 2014 LIVE show!

http://day.arduino.cc/

Arduino Day is a worldwide celebration of Arduino's first 10 years. It's 24 hours full of events -- both official and independent, anywhere around the world -- where people interested in Arduino can meet, share their experiences, and learn more.


#ArduinoD14

Node.js + Arduino, running on PC

This example show how to pass data between Node.js and Arduino bi-directionally. A Arduino Esplora is connected to a PC running Ubuntu, with Node.js running up a simple web app. Client can load the web app with Node.js Server's IP and port 8080.


From Node.js clients to server to Arduino:
- User can toggle the button to set Arduino LED ON/OFF.
- User can select color from of Arduino LCD color.

From Arduino to Node.js server to clients.
- When the Slider on Esplora changed, the setting will be sent to Node.js server to clients' progress bar on page.

Arduino code:

#include <Esplora.h>
#include <TFT.h>
#include <SPI.h>

int MAX_CMD_LENGTH = 10;
char cmd[10];
int cmdIndex;
char incomingByte;

int prevSlider = 0;

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);
    
    cmdIndex = 0;
    
}
 
void loop() {
    
    if (incomingByte=Serial.available()>0) {
      
      char byteIn = Serial.read();
      cmd[cmdIndex] = byteIn;
      
      if(byteIn=='\n'){
        //command finished
        cmd[cmdIndex] = '\0';
        //Serial.println(cmd);
        cmdIndex = 0;
        
        String stringCmd = String(cmd);
        
        if(strcmp(cmd, "LEDON")  == 0){
          //Serial.println("Command received: LEDON");
          Esplora.writeRGB(255, 255, 255);
        }else if (strcmp(cmd, "LEDOFF")  == 0) {
          //Serial.println("Command received: LEDOFF");
          Esplora.writeRGB(0, 0, 0);
        }else if(stringCmd.substring(0,4)="COL#"){
          //Serial.println("Command received: COL#");
          if(stringCmd.length()==10){
            char * pEnd;
            long int rgb = strtol(&cmd[4], &pEnd, 16);
            int r = (rgb & 0xff0000) >> 16;
            int g = (rgb & 0xff00) >> 8;
            int b = rgb & 0xff;
            //Serial.println(r);
            //Serial.println(g);
            //Serial.println(b);
            EsploraTFT.background(b,g,r);
          }
        }else{
          //Serial.println("Command received: unknown!");
        }
        
      }else{
        if(cmdIndex++ >= MAX_CMD_LENGTH){
          cmdIndex = 0;
        }
      }
    }
    
    //Read Slider
    int slider = Esplora.readSlider();
    //convert slider value from [0-1023] to [0x00-0xFF]
    slider = slider>>2 & 0xff;
    
    if(slider!=prevSlider){
      prevSlider = slider;
      
      String stringSlider = String(slider, HEX);
      Serial.println("SLD#" + stringSlider +"\n");
    }
    
}

app.js, on Node.ja server.

var app = require('http').createServer(handler), 
    io = require('socket.io').listen(app), 
    fs = require('fs'),
    os = require('os'),
    sp = require("serialport");
    
//All clients have a common status
var commonStatus = 'ON';
var commonColor = 0xffffff;
var commonSldValue = 0;
  
//init for SerialPort connected to Arduino
var SerialPort = sp.SerialPort
var serialPort = new SerialPort('/dev/ttyACM0', 
    {   baudrate: 9600,
        dataBits: 8,
        parity: 'none',
        stopBits: 1,
        flowControl: false
    });
    
var receivedData = "";
    
serialPort.on("open", function () {
    console.log('serialPort open');
    serialPort.write("LEDOFF\n");
    
    //handle data receive from Arduino
    serialPort.on('data', function(data) {
  receivedData += data.toString();
  if (receivedData.indexOf("SLD#") >= 0 
   && receivedData.indexOf("\n") >= 0) {
    
   sldValue = receivedData.substring(
    receivedData.indexOf("SLD#")+4, 
    receivedData.indexOf("\n"));
    
   receivedData = "";
   
   if ((sldValue.length == 1)
    || (sldValue.length == 2)){
    commonSldValue = parseInt("0x"+sldValue); 
    io.sockets.emit('update slider', 
       { value: commonSldValue});
    console.log('update slider: ' + commonSldValue);
   } 
  }
 });
    
});
    
//Display my IP
var networkInterfaces=os.networkInterfaces();

for (var interface in networkInterfaces) {
    
    networkInterfaces[interface].forEach(
        function(details){
            
            if (details.family=='IPv4' 
                && details.internal==false) {
                    console.log(interface, details.address);  
        }
    });
}

app.listen(8080);

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }

    res.writeHead(200);
    res.end(data);
  });
}

io.sockets.on('connection', function (socket) {
    
    //Send client with his socket id
    socket.emit('your id', 
        { id: socket.id});
    
    //Info all clients a new client caaonnected
    io.sockets.emit('on connection', 
        { client: socket.id,
          clientCount: io.sockets.clients().length,
        });
        
    //Set the current common status to the new client
    socket.emit('ack button status', { status: commonStatus });
    socket.emit('ack color', { color: commonColor });
    socket.emit('update slider', { value: commonSldValue});
    
    socket.on('button update event', function (data) {
        console.log(data.status);
        
        //acknowledge with inverted status, 
        //to toggle button text in client
        if(data.status == 'ON'){
            console.log("ON->OFF");
            commonStatus = 'OFF';
            serialPort.write("LEDON\n");
        }else{
            console.log("OFF->ON");
            commonStatus = 'ON';
            serialPort.write("LEDOFF\n");
        }
        io.sockets.emit('ack button status', 
            { status: commonStatus,
              by: socket.id
            });
    });
    
    socket.on('update color', function (data) {
  commonColor = data.color;
  console.log("set color: " + commonColor);
  var stringColorHex = "COL" + commonColor.toString(16);
  console.log("stringColorHex: " + stringColorHex);
  
  serialPort.write(stringColorHex + "\n");
  
  io.sockets.emit('ack color', 
   { color: data.color,
     by: socket.id
   });
 });
    
    //Info all clients if this client disconnect
    socket.on('disconnect', function () {
        io.sockets.emit('on disconnect', 
            { client: socket.id,
              clientCount: io.sockets.clients().length-1,
            });
    });
});

index.html

<!DOCTYPE html>
<html>
<meta name="viewport" content="width=device-width, user-scalable=no">
<head></head>
<body>
<hi>Test Node.js with socket.io</hi>
<form action="">
<input type="button" id="buttonToggle" value="ON" style="color:blue"
       onclick="toggle(this);">
</form>
<br/>
Select color: <br/>
<input id="colorpick" type="color" name="favcolor" 
 onchange="JavaScript:colorchanged()"><br>
<br/>
<progress id="progressbar" max="255"><span>0</span>%</progress>


<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect(document.location.href);
var myId;

socket.on('update slider', function (data) {
    console.log("update slider: " + data.value);
    document.getElementById("progressbar").value = data.value;
});

socket.on('on connection', function (data) {
    console.log("on connection: " + data.client);
    console.log("Number of client connected: " + data.clientCount);
});

socket.on('on disconnect',function(data) {
    console.log("on disconnect: " + data.client);
    console.log("Number of client connected: " + data.clientCount);
});

socket.on('your id',function(data) {
    console.log("your id: " + data.id);
    myId = data.id;
});

socket.on('ack button status', function (data) {
    console.log("status: " + data.status);
    
    if(myId==data.by){
        console.log("by YOU");
    }else{
        console.log("by: " + data.by);
    }
    
    if(data.status =='ON'){
        document.getElementById("buttonToggle").value="ON";
    }else{
        document.getElementById("buttonToggle").value="OFF";
    }
});

socket.on('ack color', function (data) {
    console.log("ack color: " + data.color);
    document.body.style.background = data.color;
    if(myId==data.by){
        console.log("by YOU");
    }else{
        console.log("by: " + data.by);
    }
});

function toggle(button)
{
 if(document.getElementById("buttonToggle").value=="OFF"){
  socket.emit('button update event', { status: 'OFF' });
 }
 else if(document.getElementById("buttonToggle").value=="ON"){
  socket.emit('button update event', { status: 'ON' });
 }
}

function colorchanged()
{
 //console.log("colorchanged()");
 var colorval = document.getElementById("colorpick").value;
 console.log("colorchanged(): " + colorval);
 //document.body.style.background = colorval;
 socket.emit('update color', { color: colorval });
}

</script>

</body>
</html>

Cross post with Hello Raspberry Pi, the same code run on Raspberry Pi.

Convert int to String

This example show how to convert int to String in various number base, BIN, HEX, DEC.

void setup() {
  
}

void loop() {
  int i = 1023;
  Serial.println("http://arduino-er.blogspot.com/");
  Serial.println("Test String: convert int to String");
  Serial.println();
  
  Serial.println("String(i) = " + String(i));
  Serial.println();
  
  Serial.println("String(i, BIN) = " 
      + String(i, BIN));
  Serial.println("String(i, HEX) = " 
      + String(i, HEX));
  Serial.println("String(i, DEC) = " 
      + String(i, DEC));
  Serial.println();
  
  Serial.println("String(i+i, BIN) = " 
      + String(i+i, BIN));
  Serial.println("String(i+i, HEX) = " 
      + String(i+i, HEX));
  Serial.println("String(i+i, DEC) = " 
      + String(i+i, DEC));
  Serial.println();
  
  Serial.println("String(i, BIN)+String(i, BIN) = " 
      + String(i, BIN)+String(i, BIN));
  Serial.println("String(i, HEX)+String(i, HEX) = " 
      + String(i, HEX)+String(i, HEX));
  Serial.println("String(i, DEC)+String(i, DEC) = " 
      + String(i, DEC)+String(i, DEC));
  Serial.println();
  
  delay(1000);
}

Convert int to String

Webcast recorded online now: Beyond the Arduino: Programming AVR Microcontrollers in C

The webcast "Beyond the Arduino: Programming AVR Microcontrollers in C" hold on March 18 2014, recorded and online now. This presentation will be available to audience members until June 16, 2014 at 12:30 PM Pacific Daylight Time. Visit http://oreillynet.com/pub/e/3018 to view it online, free register and log-in required.

In this webcast, dive straight into the deep end. Show you what you need to get started programming the AVR ATMega (and ATTiny) series microcontrollers, give you an overview of their built-in peripherals, and demonstrate most of the important functionality. And while the focus of this webcast is on Atmel's AVR series, nearly everything you'll learn here is transferable to other microcontrollers.

About Elliot Williams

Elliot Williams is a Ph.D. in Economics, a former government statistician, and a lifelong electronics hacker. He taught himself to program microcontrollers long before there was any such thing as an Arduino, and loves to spread the knowledge. Most recently, he is author of the Maker Media book "Make: AVR Programming, Learning to Write Software for Hardware", which is chock full of microcontroller-programming tidbits and thick enough to stun a rhino.

Web App of Node.js to control Raspberry Pi connected Arduino

This is a example to implement a web app with Node.js running on Raspberry Pi, to receive command from client, and control connected Arduino Esplora's LED. All clients share a common hardware: when a client toggle the LED, all clients will be updated accordingly.


This example should be run on any other Node.js supported platform, with changing SerialPort name. The tablet is used to log-in Raspberry Pi to start the app, for demonstrate only, not a part of the example.

You have to install socket.io and serialport modules for Node.js:
$ npm install socket.io
$ npm install serialport

app.js

var app = require('http').createServer(handler), 
    io = require('socket.io').listen(app), 
    fs = require('fs'),
    os = require('os'),
    sp = require("serialport");
  
//init for SerialPort connected to Arduino
var SerialPort = sp.SerialPort
var serialPort = new SerialPort('/dev/ttyACM0', 
    {   baudrate: 9600,
        dataBits: 8,
        parity: 'none',
        stopBits: 1,
        flowControl: false
    });
    
serialPort.on("open", function () {
    console.log('serialPort open');
    serialPort.write("LEDOFF\n");
});
    
//Display my IP
var networkInterfaces=os.networkInterfaces();

for (var interface in networkInterfaces) {
    
    networkInterfaces[interface].forEach(
        function(details){
            
            if (details.family=='IPv4' 
                && details.internal==false) {
                    console.log(interface, details.address);  
        }
    });
}

//All clients have a common status
var commonStatus = 'ON';

app.listen(8080);

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }

    res.writeHead(200);
    res.end(data);
  });
}

io.sockets.on('connection', function (socket) {
    
    //Send client with his socket id
    socket.emit('your id', 
        { id: socket.id});
    
    //Info all clients a new client caaonnected
    io.sockets.emit('on connection', 
        { client: socket.id,
          clientCount: io.sockets.clients().length,
        });
        
    //Set the current common status to the new client
    socket.emit('ack button status', { status: commonStatus });
    
    socket.on('button update event', function (data) {
        console.log(data.status);
        
        //acknowledge with inverted status, 
        //to toggle button text in client
        if(data.status == 'ON'){
            console.log("ON->OFF");
            commonStatus = 'OFF';
            serialPort.write("LEDON\n");
        }else{
            console.log("OFF->ON");
            commonStatus = 'ON';
            serialPort.write("LEDOFF\n");
        }
        io.sockets.emit('ack button status', 
            { status: commonStatus,
              by: socket.id
            });
    });
    
    //Info all clients if this client disconnect
    socket.on('disconnect', function () {
        io.sockets.emit('on disconnect', 
            { client: socket.id,
              clientCount: io.sockets.clients().length-1,
            });
    });
});

index.html

<html>
<meta name="viewport" content="width=device-width, user-scalable=no">
<head></head>
<body>
<hi>Test Node.js with socket.io</hi>
<form action="">
<input type="button" id="buttonToggle" value="ON" style="color:blue"
       onclick="toggle(this);">
</form>
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect(document.location.href);
var myId;

socket.on('on connection', function (data) {
    console.log("on connection: " + data.client);
    console.log("Number of client connected: " + data.clientCount);
});

socket.on('on disconnect',function(data) {
    console.log("on disconnect: " + data.client);
    console.log("Number of client connected: " + data.clientCount);
});

socket.on('your id',function(data) {
    console.log("your id: " + data.id);
    myId = data.id;
});

socket.on('ack button status', function (data) {
    console.log("status: " + data.status);
    
    if(myId==data.by){
        console.log("by YOU");
    }else{
        console.log("by: " + data.by);
    }
    
    if(data.status =='ON'){
        document.getElementById("buttonToggle").value="ON";
    }else{
        document.getElementById("buttonToggle").value="OFF";
    }
});

function toggle(button)
{
 if(document.getElementById("buttonToggle").value=="OFF"){
  socket.emit('button update event', { status: 'OFF' });
 }
 else if(document.getElementById("buttonToggle").value=="ON"){
  socket.emit('button update event', { status: 'ON' });
 }
}
</script>

</body>
</html>

Arduino code, same as in last post.

#include <Esplora.h>
#include <TFT.h>
#include <SPI.h>

int MAX_CMD_LENGTH = 10;
char cmd[10];
int cmdIndex;
char incomingByte;

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);
    
    cmdIndex = 0;
    
}
 
void loop() {
    
    if (incomingByte=Serial.available()>0) {
      
      char byteIn = Serial.read();
      cmd[cmdIndex] = byteIn;
      
      if(byteIn=='\n'){
        //command finished
        cmd[cmdIndex] = '\0';
        Serial.println(cmd);
        cmdIndex = 0;
        
        if(strcmp(cmd, "LEDON")  == 0){
          Serial.println("Command received: LEDON");
          Esplora.writeRGB(255, 255, 255);
        }else if (strcmp(cmd, "LEDOFF")  == 0) {
          Serial.println("Command received: LEDOFF");
          Esplora.writeRGB(0, 0, 0);
        }else{
          Serial.println("Command received: unknown!");
        }
        
      }else{
        if(cmdIndex++ >= MAX_CMD_LENGTH){
          cmdIndex = 0;
        }
      }
    }
    
}

Cross-post with Hello Raspberry Pi

Next: Implement bi-directiuonal communication between Node.js and Arduino.

Arduino detect string command from serial port

This example receive char and detect command terminal '\n', and compare with predefined command ("LEDON" and "LEDOFF") with strcmp() function, to turn on/off Esplora's on-board LED accordingly.



serialReadCmd.ino

#include <Esplora.h>
#include <TFT.h>
#include <SPI.h>

int MAX_CMD_LENGTH = 10;
char cmd[10];
int cmdIndex;
char incomingByte;

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);
    
    cmdIndex = 0;
    
}
 
void loop() {
    
    if (incomingByte=Serial.available()>0) {
      
      char byteIn = Serial.read();
      cmd[cmdIndex] = byteIn;
      
      if(byteIn=='\n'){
        //command finished
        cmd[cmdIndex] = '\0';
        Serial.println(cmd);
        cmdIndex = 0;
        
        if(strcmp(cmd, "LEDON")  == 0){
          Serial.println("Command received: LEDON");
          Esplora.writeRGB(255, 255, 255);
        }else if (strcmp(cmd, "LEDOFF")  == 0) {
          Serial.println("Command received: LEDOFF");
          Esplora.writeRGB(0, 0, 0);
        }else{
          Serial.println("Command received: unknown!");
        }
        
      }else{
        if(cmdIndex++ >= MAX_CMD_LENGTH){
          cmdIndex = 0;
        }
      }
    }
    
}

What Is Open Source Hardware?

This video describes the attributes of open source hardware to the general public. This video is officially released by the Open Source Hardware Association.

Software / Hardware / Everywhere

Tim O'Reilly & Jim Stogdill Explore Software - Hardware - Everywhere



We've reached another tipping point in history. The collision of hardware and software—the confluence of the virtual and physical—changes everything from products, industrial practices, and business models to appliances, automobiles, and job opportunities. Today's Internet of Everything is a classic market disruption, with immense unimagined opportunities and more than a few thorny challenges.

Join Tim O'Reilly, founder and CEO of O'Reilly Media, and Jim Stogdill, who leads O'Reilly's Solid, in a live-streamed conversation about the current state of the convergence of hardware and software, what this means beyond the Internet of Things, new promises and pitfalls, some opportunities we may not have thought of yet, and a vision for the future. Register free to get the livestream link and join this conversation.

http://solidcon.com/

Arduino + Raspberry Pi + Node.js

Cross-post with Hello Raspberry Pi: Communication between RAspberry Pi and Arduino, using Node.js.

This example demonstrate how to send data between Raspberry Pi and Arduino Esplora board via USB, using Node.js.


Node.js script run on Raspberry Pi.

//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);
        });
});

Arduino side, (same as in the post "Serial communication between Arduino Esplora and PC").

#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 = "";
    }
}

Bi-direction serial communication using java-simple-serial-connector

Last post "JavaFX + java-simple-serial-connector + Arduino" implement simple one way communication from PC run JavaFX to Arduino. This example implement bi-direction sending and receiving between PC and Arduino, using java-simple-serial-connector.



To implement receiving, we have to implement SerialPortEventListener, and add it with serialPort.addEventListener().

package javafx_jssc;

import java.io.UnsupportedEncodingException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.TextField;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.stage.WindowEvent;
import jssc.SerialPort;
import jssc.SerialPortEvent;
import jssc.SerialPortEventListener;
import jssc.SerialPortException;
import jssc.SerialPortList;

public class JavaFX_jSSC extends Application {

    SerialPort serialPort;
    ObservableList<String> portList;

    ComboBox comboBoxPorts;
    TextField textFieldOut, textFieldIn;
    Button btnOpenSerial, btnCloseSerial, btnSend;

    private void detectPort() {

        portList = FXCollections.observableArrayList();

        String[] serialPortNames = SerialPortList.getPortNames();
        for (String name : serialPortNames) {
            System.out.println(name);
            portList.add(name);
        }
    }

    @Override
    public void start(Stage primaryStage) {

        detectPort();

        comboBoxPorts = new ComboBox(portList);
        textFieldOut = new TextField();
        textFieldIn = new TextField();

        btnOpenSerial = new Button("Open Serial Port");
        btnCloseSerial = new Button("Close Serial Port");
        btnSend = new Button("Send");
        btnSend.setDisable(true);   //default disable before serial port open
        
        btnOpenSerial.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent t) {
                closeSerialPort();              //close serial port before open
                if(openSerialPort()){
                    btnSend.setDisable(false);
                }else{
                    btnSend.setDisable(true);
                }
            }
        });
        
        btnCloseSerial.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent t) {
                closeSerialPort();
                btnSend.setDisable(true);
            }
        });

        btnSend.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent t) {
                
                if(serialPort != null && serialPort.isOpened()){
                    try {
                        String stringOut = textFieldOut.getText();
                        serialPort.writeBytes(stringOut.getBytes());
                    } catch (SerialPortException ex) {
                        Logger.getLogger(JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
                    }
                }else{
                    System.out.println("Something wrong!");
                }
            }
        });

        VBox vBox = new VBox();
        vBox.getChildren().addAll(
                comboBoxPorts,
                textFieldOut,
                textFieldIn,
                btnOpenSerial,
                btnCloseSerial,
                btnSend);

        StackPane root = new StackPane();
        root.getChildren().add(vBox);

        Scene scene = new Scene(root, 300, 250);

        primaryStage.setOnCloseRequest(new EventHandler<WindowEvent>() {

            @Override
            public void handle(WindowEvent t) {
                closeSerialPort();
            }
        });

        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }

    private boolean openSerialPort() {
        boolean success = false;
        
        if (comboBoxPorts.getValue() != null
                && !comboBoxPorts.getValue().toString().isEmpty()) {
            try {
                serialPort = new SerialPort(comboBoxPorts.getValue().toString());
                
                serialPort.openPort();
                serialPort.setParams(
                        SerialPort.BAUDRATE_9600,
                        SerialPort.DATABITS_8,
                        SerialPort.STOPBITS_1,
                        SerialPort.PARITY_NONE);
                
                serialPort.addEventListener(new MySerialPortEventListener());
                
                success = true;
            } catch (SerialPortException ex) {
                Logger.getLogger(JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        return success;
    }

    private void closeSerialPort() {
        if (serialPort != null && serialPort.isOpened()) {
            try {
                serialPort.closePort();
            } catch (SerialPortException ex) {
                Logger.getLogger(JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        
        serialPort = null;
    }
    
    class MySerialPortEventListener implements SerialPortEventListener {

        @Override
        public void serialEvent(SerialPortEvent serialPortEvent) {
            
            if(serialPortEvent.isRXCHAR()){
                try {
                    int byteCount = serialPortEvent.getEventValue();
                    byte bufferIn[] = serialPort.readBytes(byteCount);
                    
                    String stringIn = "";
                    try {
                        stringIn = new String(bufferIn, "UTF-8");
                    } catch (UnsupportedEncodingException ex) {
                        Logger.getLogger(JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
                    }
                    textFieldIn.setText(stringIn);
                    
                } catch (SerialPortException ex) {
                    Logger.getLogger(JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
                }
                
            }
            
        }
        
    }
}

Arduino Esplora side, refer to previous post.

bateske Arduboy:The Interactive Digital Business Card

A revolution in minimalist circuit board art design.

• Barebones Arduino
• OLED Screen
• Piezo Speaker
• Capacitive Input Buttons
• 9+ Hours Playtime
• 1.6 millimeters total thickness

http://www.bateske.com/Arduboy/

JavaFX + java-simple-serial-connector + Arduino

This example implement a simple Java application using java-simple-serial-connector library (jSSC) , with JavaFX user interface, send bytes to Arduino Esplora via USB.

package javafx_jssc;

import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.TextField;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import jssc.SerialPort;
import jssc.SerialPortException;
import jssc.SerialPortList;

public class JavaFX_jSSC extends Application {
    
    ObservableList<String> portList;
    
    private void detectPort(){
        
        portList = FXCollections.observableArrayList();

        String[] serialPortNames = SerialPortList.getPortNames();
        for(String name: serialPortNames){
            System.out.println(name);
            portList.add(name);
        }
    }
    
    @Override
    public void start(Stage primaryStage) {
        
        detectPort();

        final ComboBox comboBoxPorts = new ComboBox(portList);
        final TextField textFieldOut = new TextField();
        Button btnSend = new Button("Send");
        
        btnSend.setOnAction(new EventHandler<ActionEvent>() {

            @Override
            public void handle(ActionEvent t) {

                if(comboBoxPorts.getValue() != null && 
                    !comboBoxPorts.getValue().toString().isEmpty()){
                    
                    String stringOut = textFieldOut.getText();
                    
                    try {
                        SerialPort serialPort = 
                            new SerialPort(comboBoxPorts.getValue().toString());                        
                        
                        serialPort.openPort();
                        serialPort.setParams(
                                SerialPort.BAUDRATE_9600,
                                SerialPort.DATABITS_8,
                                SerialPort.STOPBITS_1,
                                SerialPort.PARITY_NONE);
                        serialPort.writeBytes(stringOut.getBytes());
                        serialPort.closePort();
                        
                    } catch (SerialPortException ex) {
                        Logger.getLogger(
                            JavaFX_jSSC.class.getName()).log(Level.SEVERE, null, ex);
                    }
                    
                }else{
                    System.out.println("No SerialPort selected!");
                }
            }
        });
        
        VBox vBox = new VBox();
        vBox.getChildren().addAll(
                comboBoxPorts, 
                textFieldOut, 
                btnSend);
        
        StackPane root = new StackPane();
        root.getChildren().add(vBox);
        
        Scene scene = new Scene(root, 300, 250);
        
        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
    
}

Arduino code in Esplora side (same as in the post "Serial communication between Arduino Esplora and PC").

#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 = "";
    }
}

Read last post for Install and test java-simple-serial-connector with Arduino.

Next:
- Bi-direction serial communication using java-simple-serial-connector

Install and test java-simple-serial-connector with Arduino, on Ubuntu

As the new Arduino 1.5.6 BETA replaced RXTX library with JSSC (https://code.google.com/p/java-simple-serial-connector/), this video show how to install JSSC and setup on Netbeans, build a Hello World run on Ubuntu Linux, to send data to Arduino Esplora board. Actually the setup steps and example code follow https://code.google.com/p/java-simple-serial-connector/wiki/jSSC_Start_Working.

The last version of jSSC can be downloaded here: http://code.google.com/p/java-simple-serial-connector/downloads/list

In order to work on Ubuntu, modify the example code to change SerialPort to "/dev/ttyACM0".

package java_testjssc;

import jssc.SerialPort;
import jssc.SerialPortException;

public class Java_testjSSC {

    public static void main(String[] args) {
        SerialPort serialPort = new SerialPort("/dev/ttyACM0");
        try {
            System.out.println("Port opened: " + serialPort.openPort());
            System.out.println("Params setted: " + serialPort.setParams(9600, 8, 1, 0));
            System.out.println("\"Hello World!!!\" successfully writen to port: " + serialPort.writeBytes("Hello World!!!".getBytes()));
            System.out.println("Port closed: " + serialPort.closePort());
        }
        catch (SerialPortException ex){
            System.out.println(ex);
        }
    }
    
}

The Arduino side code, refer to the post "Serial communication between Arduino Esplora and PC".

Next: A simple Java application using java-simple-serial-connector library (jSSC) , with JavaFX user interface, send bytes to Arduino Esplora via USB.

Related: Use jSSC (Java Simple Serial Connector) on Windows 8.1