Bi-direction communication between Arduino and PC using Java + jSSC

This example show Bi-direction communication between Arduino Uno and PC using Java + javaFX + jSSC:
Arduino to PC: Arduino Uno analog input, display on JavaFX LineChart
PC to Arduino: Button to control Arduino Uno on-board LED


Before start, you have to Prepare jSSC on your NetBeans project.

Arduino side: AnalogInputToUSB.ino, run on Arduino Uno.

/* * AnalogInputUSB * Read analog input from analog pin 0 * and send data to USB */ int ledPin = 13; int analogPin = A0; int analogValue = 0; int incomingByte = 0; void setup() { pinMode(ledPin, OUTPUT); Serial.begin(9600); } void loop() { if (Serial.available() > 0) { incomingByte = Serial.read(); if(incomingByte & 0x01){ digitalWrite(ledPin, HIGH); }else{ digitalWrite(ledPin, LOW); } } analogValue = analogRead(analogPin); //Read analog input analogValue = map(analogValue, 0, 1023, 0, 255); Serial.write(analogValue); //write as byte, to USB delay(100); }a 

PC Side, JavaFX_jssc_Uno.java

/* * Example of using jSSC library to handle serial port * Receive number from Arduino via USB/Serial and display on Label */ package javafx_jssc_uno; import java.util.logging.Level; import java.util.logging.Logger; import javafx.application.Application; import javafx.application.Platform; import javafx.beans.value.ChangeListener; import javafx.beans.value.ObservableValue; import javafx.collections.FXCollections; import javafx.collections.ObservableList; import javafx.event.ActionEvent; import javafx.scene.Scene; import javafx.scene.chart.LineChart; import javafx.scene.chart.NumberAxis; import javafx.scene.chart.XYChart; import javafx.scene.control.Button; import javafx.scene.control.ComboBox; import javafx.scene.control.Label; import javafx.scene.control.ToggleButton; import javafx.scene.layout.StackPane; import javafx.scene.layout.VBox; import javafx.scene.text.Font; import javafx.stage.Stage; import jssc.SerialPort; import static jssc.SerialPort.MASK_RXCHAR; import jssc.SerialPortEvent; import jssc.SerialPortException; import jssc.SerialPortList; public class JavaFX_jssc_Uno extends Application { SerialPort arduinoPort = null; ObservableList<String> portList; ToggleButton tbLED13; Label labelValue; final int NUM_OF_POINT = 50; XYChart.Series series; 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) { labelValue = new Label(); labelValue.setFont(new Font("Arial", 28)); detectPort(); final ComboBox comboBoxPorts = new ComboBox(portList); comboBoxPorts.valueProperty() .addListener(new ChangeListener<String>() { @Override public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) { System.out.println(newValue); disconnectArduino(); connectArduino(newValue); tbLED13.setSelected(false); } }); //Toggle Button to control LED on Arduino tbLED13 = new ToggleButton("Arduino LED 13"); tbLED13.setOnAction((ActionEvent event) -> { updateLED13(); }); //LineChart final NumberAxis xAxis = new NumberAxis(); final NumberAxis yAxis = new NumberAxis(); yAxis.setLabel("Voltage"); final LineChart<Number,Number> lineChart = new LineChart<>(xAxis,yAxis); lineChart.setTitle("Arduino Uno A0 Analog Input"); series = new XYChart.Series(); series.setName("A0 analog input"); lineChart.getData().add(series); lineChart.setAnimated(false); //pre-load with dummy data for(int i=0; i<NUM_OF_POINT; i++){ series.getData().add(new XYChart.Data(i, 0)); } // VBox vBox = new VBox(); vBox.getChildren().addAll( comboBoxPorts, tbLED13, labelValue, lineChart); StackPane root = new StackPane(); root.getChildren().add(vBox); Scene scene = new Scene(root, 500, 400); primaryStage.setTitle( "arduino-er.blogspot.com: Java + JavaFX + jSSC demo"); primaryStage.setScene(scene); primaryStage.show(); } private void updateLED13(){ try { if(tbLED13.isSelected()){ if(arduinoPort != null){ arduinoPort.writeByte((byte)0x01); System.out.println("LED 13 ON"); }else{ System.out.println("arduinoPort not connected!"); } }else { if(arduinoPort != null){ arduinoPort.writeByte((byte)0x00); System.out.println("LED 13 OFF"); }else{ System.out.println("arduinoPort not connected!"); } } }catch (SerialPortException ex) { Logger.getLogger(JavaFX_jssc_Uno.class.getName()) .log(Level.SEVERE, null, ex); } } public void shiftSeriesData(float newValue) { for(int i=0; i<NUM_OF_POINT-1; i++){ XYChart.Data<String, Number> ShiftDataUp = (XYChart.Data<String, Number>)series.getData().get(i+1); Number shiftValue = ShiftDataUp.getYValue(); XYChart.Data<String, Number> ShiftDataDn = (XYChart.Data<String, Number>)series.getData().get(i); ShiftDataDn.setYValue(shiftValue); } XYChart.Data<String, Number> lastData = (XYChart.Data<String, Number>)series.getData().get(NUM_OF_POINT-1); lastData.setYValue(newValue); } public boolean connectArduino(String port){ System.out.println("connectArduino"); boolean success = false; SerialPort serialPort = new SerialPort(port); try { serialPort.openPort(); serialPort.setParams( SerialPort.BAUDRATE_9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); serialPort.setEventsMask(MASK_RXCHAR); serialPort.addEventListener((SerialPortEvent serialPortEvent) -> { if(serialPortEvent.isRXCHAR()){ try { byte[] b = serialPort.readBytes(); int value = b[0] & 0xff; //convert to int String st = String.valueOf(value); //Update label in ui thread Platform.runLater(() -> { labelValue.setText(st); shiftSeriesData((float)value * 5/255); //in 5V scale }); } catch (SerialPortException ex) { Logger.getLogger(JavaFX_jssc_Uno.class.getName()) .log(Level.SEVERE, null, ex); } } }); arduinoPort = serialPort; success = true; } catch (SerialPortException ex) { Logger.getLogger(JavaFX_jssc_Uno.class.getName()) .log(Level.SEVERE, null, ex); System.out.println("SerialPortException: " + ex.toString()); } return success; } public void disconnectArduino(){ System.out.println("disconnectArduino()"); if(arduinoPort != null){ try { arduinoPort.removeEventListener(); if(arduinoPort.isOpened()){ arduinoPort.closePort(); } arduinoPort = null; } catch (SerialPortException ex) { Logger.getLogger(JavaFX_jssc_Uno.class.getName()) .log(Level.SEVERE, null, ex); } } } @Override public void stop() throws Exception { disconnectArduino(); super.stop(); } public static void main(String[] args) { launch(args); } } 

Connect a potentiometer in Arduino Uno side to set analog input A0.

Next:
- Run it remotely on Raspberry Pi 2.