JavaFX + jSSC - read byte from Arduino Uno, read from Analog Input

This example show how to use Java + jSSC + JavaFX running on PC/Windows 10, read bytes from USB/Serial. The data sent from Arduino Uno by reading analog input. The PC and Arduino Uno connected with USB.


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

Java code, run on 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.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.control.Label;
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;
    
    Label labelValue;
     
    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", 150));
        
        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);
            }

        });
        
        VBox vBox = new VBox();
        vBox.getChildren().addAll(
                comboBoxPorts, labelValue);
        
        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 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);  
                        });
                        
                    } 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();
                }
                
            } 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);
    }
    
}

Arduino Uno side - AnalogInputToUSB.ino

/*
 * AnalogInputUSB
 * Read analog input from analog pin 0
 * and send data to USB
 */

int ledPin = 13;
int analogPin = A0;
int analogValue = 0;

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  digitalWrite(ledPin, HIGH);
  
  analogValue = analogRead(analogPin);  //Read analog input
  analogValue = map(analogValue, 0, 1023, 0, 255);
  Serial.write(analogValue);            //write as byte, to USB
  
  digitalWrite(ledPin, LOW);
  delay(1000);
}

Connect a potentiometer in Analog Input A0 as input.

Next:
- JavaFX + jSSC - read byte from Arduino Uno, display in LineChart