java读串口数据

https://www.360docs.net/doc/5113047697.html,/article.asp?id=90

这个简单的程序包括以下文件：

IMU.java (主程序)
ReadBuffer.java (从缓冲区读取一个消息)
ReadSerial.java (读取串口数据并放入缓冲区)
SerialBuffer.java (缓冲区)
WriteSerial.java (不断的往串口送星号'*')

测试程序：

SendCom.java (将一个数据文件往串口发送)
SEND.TXT (供测试用的数据文件)

在这个通讯程序中使用了一个简单的协议，既不同的消息之间用星号'*'作为分隔。这个程序中的问题是ReadSerial进程和WriteSerial进程不能够同时启动，出错信息是不能够打开串口，因为同样一个串口不能够同时被打开两次(在ReadSerial中声明了FileReader和在WriteSerial中声明了FileWriter)。这样是不能够实现全双工通讯的。

/*
*
* IMU.java 1.0
* Main Program for Serial Communication
*
* Created: March 27, 2001
*
* Author : Qingye Jiang (John)
* American GNC Corporation
* 888 Easy St, Simi Valley CA 93065-1812
*
* Contact: (805) 582-0582 (Tel), (805) 582-0098 (Fax)
* qjiang@https://www.360docs.net/doc/5113047697.html,
*
*/

import java.io.*;

class IMU
{
public static void main(String[] args)
{
//TO DO: Add your JAVA codes here

File ComPort = new File("COM1");

SerialBuffer SB = new SerialBuffer();
ReadSerial r1 = new ReadSerial(SB, ComPort);
ReadBuffer r2 = new ReadBuffer(SB);
WriteSerial r3 = new WriteSerial(ComPort);

r1.start();
r2.start();
r3.start();
}
}

/*
*
* ReadBuffer.java 1.0
* Program to Read the Serial Buffer
*
* Created: March 27, 2001
*
* Author : Qingye Jiang (John)
* American GNC Corporation
* 888 Easy St, Simi Valley CA 93065-1812
*
* Contact: (805) 582-0582 (Tel), (805) 582-0098 (Fax)
* qjiang@https://www.360docs.net/doc/5113047697.html,

*
*/

import java.io.*;

public class ReadBuffer extends Thread
{
private SerialBuffer ComBuffer;

public ReadBuffer(SerialBuffer SB)
{
ComBuffer = SB;
}

public void run()
{
String Msg;

while (true)
{
Msg = ComBuffer.GetMsg();
System.out.println(Msg);
}

}
}

/*
*
* ReadSerial.java 1.0
* Program to read characters from the serial port and put it
* to the buffer
*
* Created: March 27, 2001
*
* Author : Qingye Jiang (John)
* American GNC Corporation
* 888 Easy St, Simi Valley CA 93065-1812
*
* Contact: (805) 582-0582 (Tel), (805) 582-0098 (Fax)
* qjiang@https://www.360docs.net/doc/5113047697.html,
*
*/

import java.io.*;

public class ReadSerial extends Thread
{
private SerialBuffer ComBuffer;
private File ComPort;

public ReadSerial(SerialBuffer SB, File Port)
{
ComBuffer = SB;
ComPort = Port;
}

public void run()
{
int c;
try
{
FileRead

er in = new FileReader(ComPort);

while (true)
{
c = in.read();
ComBuffer.PutChar(c);
}
try
{
FileReader in = new FileReader(ComPort);
while (true)
{
c = in.read();

ComBuffer.PutChar(c);
}
} catch (IOException e) {}
}
}


/*
*
* SerialBuffer.java 1.0
* Class that implements the serial buffer
*
* Created: March 27, 2001
*
* Author : Qingye Jiang (John)
* American GNC Corporation
* 888 Easy St, Simi Valley CA 93065-1812
*
* Contact: (805) 582-0582 (Tel), (805) 582-0098 (Fax)
* qjiang@https://www.360docs.net/doc/5113047697.html,

*
*/

public class SerialBuffer
{
private String Content = "";
private String CurrentMsg, TempContent;
private boolean available = false;

public synchronized String GetMsg()
{
int SepMark;

if ((SepMark = Content.indexOf('*')) == -1)
{
available = false;
while (available == false)
{
try
{
wait();
} catch (InterruptedException e) { }
}
SepMark = Content.indexOf('*');
}

CurrentMsg = Content.substring(0, SepMark);
TempContent = Content.substring(SepMark+1);
Content = TempContent;
notifyAll();
return CurrentMsg;
}

public synchronized void PutChar(int c)
{
Character d = new Character((char) c);
Content = Content.concat(d.toString());
if (c == '*')
{
available = true;
}
notifyAll();
}
}


/*
*
* WriteSerial.java 1.0
* Program to send a character to the serial port
*
* Created: March 27, 2001
*
* Author : Qingye Jiang (John)
* American GNC Corporation
* 888 Easy St, Simi Valley CA 93065-1812
*
* Contact: (805) 582-0582 (Tel), (805) 582-0098 (Fax)
* qjiang@https://www.360docs.net/doc/5113047697.html,
*
*/

import java.io.*;

public class WriteSerial extends Thread
{
private SerialBuffer ComBuffer;
private File ComPort;

public WriteSerial(File Port)
{
ComPort = Port;
}

public void run()
{
int c;
try
{
FileWriter out = new FileWriter(ComPort);
while (true)
{
out.write('*');
}
} catch (IOException e)
{
System.out.println(e.getMessage());
}
}
}

import java.io.*;

public class SendCom
{
public static void main(String[] args)
{

File OutFile = new File("SEND.TXT");
File ComPort = new File("COM2");

int c;

try
{
FileReader in = new FileReader(OutFile);
FileWriter out = new FileWriter(C

omPort);
while ((c = in.read()) != -1)
out.write(c);
in.close();
out.close();
} catch (IOException e) {}

}
}


SEND.TXT*

This is a sample of the data file for program testing. *

It should be in the same directory as the SendCom.class file.*

When you run this sample program, connect your COM1 and COM2 with a
serial cable so that you can test this program on one machine. If
you have two machines, you can connect the two machine via a serial
cable and test it. Modified the definition of ComPort in the program
if necessary. *

Thank you for testing this program. If you have any suggestions please
kindly let me know. *