// START SNIPPET: serial-snippet
/*
* #%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 - 2017 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
* .
* #L%
*/
import com.pi4j.io.serial.*;
import com.pi4j.util.CommandArgumentParser;
import com.pi4j.util.Console;
import java.io.IOException;
import java.time.LocalTime;
/**
* This example code demonstrates how to perform serial communications using the Raspberry Pi.
*
* @author Robert Savage
*/
public class Test {
/**
* 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();
System.out.println("Initialization...");
// create an instance of the serial communications class
final Serial serial = SerialFactory.createInstance();
// create and register the serial data listener
serial.addListener(new SerialDataEventListener() {
int pos = 0;
char var = '\0';
byte high = 0;
byte low = 0;
short val;
@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
{
byte[] bytes = event.getBytes();
for (byte b : bytes)
{
// System.out.print("~~" + (char)b + " ");
switch (this.pos)
{
case 0: {
if (b == '\n')
{
// System.out.println("newline");
this.pos++;
continue;
}
break;
}
case 1: {
if (b == 'X' || b == 'Y' || b == 'Z')
{
this.pos++;
this.var = (char)b;
continue;
}
break;
}
case 2: {
if (b == '=')
{
this.pos++;
continue;
}
break;
}
case 3: {
this.high = b;
this.pos++;
continue;
//break;
}
case 4: {
this.low = b;
//Float val = map((float) this.val, 0, 1023, -3, 3);
if (this.var == 'X')
System.out.println(LocalTime.now());
System.out.println(this.var + " = " + adxl345(this.high, this.low) + " milligravities");
break;
}
}
this.pos = 0;
}
// System.out.println("\nEnd of for");
}
catch (IOException e)
{
e.printStackTrace();
}
}
});
try {
// create serial config object
SerialConfig config = new SerialConfig();
System.out.println("SerialPort.getDefaultPort(): " + SerialPort.getDefaultPort());
// 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("/dev/serial0")
.baud(Baud._115200)
.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
// 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(true)
{
// wait 1 second before continuing
Thread.sleep(1000);
}
}
catch(IOException ex)
{
System.out.println(" ==>> SERIAL SETUP FAILED : " + ex.getMessage());
return;
}
}
public static float map(float x, float in_min, float in_max, float out_min, float out_max)
{
return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}
public static double adxl345(byte high, byte low)
{
short val = (short) ((high & 0xFF) << 8);
val += (short)(low & 0xFF);
double conv = (val * 3.9);
return conv;
}
public static float adxl337(byte high, byte low)
{
return 0;
}
}
// END SNIPPET: serial-snippet