Rs232-SerialPort.java

/*
 * #%L
 * **********************************************************************
 * ORGANIZATION  :  Pi4J
 * PROJECT       :  Pi4J :: Java Examples
 * FILENAME      :  SerialExample.java
 *
 * This file is part of the Pi4J project. More information about
 * this project can be found here:  http://www.pi4j.com/
 * **********************************************************************
 * %%
 * Copyright (C) 2012 - 2018 Pi4J
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 *
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
 * #L%
 */

//https://github.com/Pi4J/pi4j/blob/master/pi4j-example/src/main/java/SerialExample.java
//http://pi4j.com/example/serial.html
import com.pi4j.io.serial.*;
import com.pi4j.util.CommandArgumentParser;
import com.pi4j.util.Console;

import java.io.IOException;
import java.util.Date;

/**
 * This example code demonstrates how to perform serial communications using the
 * Raspberry Pi.
 *
 * @author Robert Savage
 */
public class Rs232-SerialPort {

	/**
	 * This example program supports the following optional command
	 * arguments/options: "--device (device-path)" [DEFAULT: /dev/ttyAMA0] "--baud
	 * (baud-rate)" [DEFAULT: 38400] "--data-bits (5|6|7|8)" [DEFAULT: 8] "--parity
	 * (none|odd|even)" [DEFAULT: none] "--stop-bits (1|2)" [DEFAULT: 1]
	 * "--flow-control (none|hardware|software)" [DEFAULT: none]
	 *
	 * @param args
	 * @throws InterruptedException
	 * @throws IOException
	 */
	public static void main(String args[]) throws InterruptedException, IOException {

		// !! ATTENTION !!
		// By default, the serial port is configured as a console port
		// for interacting with the Linux OS shell. If you want to use
		// the serial port in a software program, you must disable the
		// OS from using this port.
		//
		// Please see this blog article for instructions on how to disable
		// the OS console for this port:
		// https://www.cube-controls.com/2015/11/02/disable-serial-port-terminal-output-on-raspbian/

		// create Pi4J console wrapper/helper
		// (This is a utility class to abstract some of the boilerplate code)
		final Console console = new Console();

		// print program title/header
		console.title("<-- The Pi4J Project -->", "Serial Communication Example");

		// allow for user to exit program using CTRL-C
		console.promptForExit();

		// create an instance of the serial communications class
		final Serial serial = SerialFactory.createInstance();

		// create and register the serial data listener
		serial.addListener(new SerialDataEventListener() {
			@Override
			public void dataReceived(SerialDataEvent event) {

				// NOTE! - It is extremely important to read the data received from the
				// serial port. If it does not get read from the receive buffer, the
				// buffer will continue to grow and consume memory.

				// print out the data received to the console
				try {
					console.println("[HEX DATA]   " + event.getHexByteString());
					console.println("[ASCII DATA] " + event.getAsciiString());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		});

		try {
			// create serial config object
			SerialConfig config = new SerialConfig();

			// set default serial settings (device, baud rate, flow control, etc)
			//
			// by default, use the DEFAULT com port on the Raspberry Pi (exposed on GPIO
			// header)
			// NOTE: this utility method will determine the default serial port for the
			// detected platform and board/model. For all Raspberry Pi models
			// except the 3B, it will return "/dev/ttyAMA0". For Raspberry Pi
			// model 3B may return "/dev/ttyS0" or "/dev/ttyAMA0" depending on
			// environment configuration.
			config.device(SerialPort.getDefaultPort()).baud(Baud._38400).dataBits(DataBits._8).parity(Parity.NONE)
					.stopBits(StopBits._1).flowControl(FlowControl.NONE);

			// parse optional command argument options to override the default serial
			// settings.
			if (args.length > 0) {
				config = CommandArgumentParser.getSerialConfig(config, args);
			}

			// display connection details
			console.box(" Connecting to: " + config.toString(),
					" We are sending ASCII data on the serial port every 1 second.",
					" Data received on serial port will be displayed below.");

			// open the default serial device/port with the configuration settings
			serial.open(config);

			// continuous loop to keep the program running until the user terminates the
			// program
			while (console.isRunning()) {
				try {
					// write a formatted string to the serial transmit buffer
					serial.write("CURRENT TIME: " + new Date().toString());

					// write a individual bytes to the serial transmit buffer
					serial.write((byte) 13);
					serial.write((byte) 10);

					// write a simple string to the serial transmit buffer
					serial.write("Second Line");

					// write a individual characters to the serial transmit buffer
					serial.write('\r');
					serial.write('\n');

					// write a string terminating with CR+LF to the serial transmit buffer
					serial.writeln("Third Line");
				} catch (IllegalStateException ex) {
					ex.printStackTrace();
				}

				// wait 1 second before continuing
				Thread.sleep(1000);
			}

		} catch (IOException ex) {
			console.println(" ==>> SERIAL SETUP FAILED : " + ex.getMessage());
			return;
		}
	}
}