com0com RS232 terminal Java program

Question

i made a JAVA program that runs on a computer with 2 RS232 ports

it works pretty good i connected 2 devices that comunicate with eachother trough RS232 i put the computer between the cable

you can see everything getting send on a terminal window

but after a random amount of time 1 device stops responding on queries

normally device 1 sends query 1 and device responds

but after some time device starts sending query 2 and device 2 doesn't respond anymore

here is a capture: first column: com port id second column: decimal presentation of the character third column: visualization of characters

any idea's why this is not working? I'm planning on making the terminal program open source in the future

EDIT: i didn't post any code because the code works only stops working after 5min - 1 hour

here is the connection code: CommPortIdentifier portIdentifier; portIdentifier = CommPortIdentifier.getPortIdentifier("COM1"); InputStream inCom1; InputStream inCom2; if (portIdentifier.isCurrentlyOwned()) { addError("COM1 in use!, please restart"); } else { SerialPort serialPort = (SerialPort) portIdentifier.open("Main", 2000); //19200 8n1 serialPort.setSerialPortParams(19200, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); // CTS/RTS handshaking serialPort.setFlowControlMode(SerialPort.FLOWCONTROL_RTSCTS_IN | SerialPort.FLOWCONTROL_RTSCTS_OUT); //set sender Com1Sender.setWriterStream(serialPort.getOutputStream()); //set reciever // new com1_recieve(serialPort.getInputStream()).start();

        inCom1 = serialPort.getInputStream();

        portIdentifier = CommPortIdentifier.getPortIdentifier("COM2");
        if (portIdentifier.isCurrentlyOwned()) {
            addError("COM2 in use!, please restart");
        } else {
            serialPort = (SerialPort) portIdentifier.open("Main2", 2001);
            //19200 8n1
            serialPort.setSerialPortParams(19200, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
            // CTS/RTS handshaking
            serialPort.setFlowControlMode(SerialPort.FLOWCONTROL_RTSCTS_IN | SerialPort.FLOWCONTROL_RTSCTS_OUT);
            //set sender
            Com2Sender.setWriterStream(serialPort.getOutputStream());
            //set reciever
    //              new com2_recieve(serialPort.getInputStream()).start();

            inCom2 = serialPort.getInputStream();
            new Reciever(inCom1, inCom2).start();
        }
    }

this is the reciever: public class Reciever extends Thread {

        InputStream inCom1;
        InputStream inCom2;

        public Reciever(InputStream inCom1, InputStream inCom2) {
            this.inCom1 = inCom1;
            this.inCom2 = inCom2;
        }

        @Override
        public void run() {
            try {
                int b1;
                int b2;
                while (true) {
                    // if stream is not bound in.read() method returns -1

                    //dect
                    while ((b1 = inCom1.read()) != -1) {

                        //send trough to com2
                        Com2Sender.send(new byte[]{(byte) b1});

                        Main.addText(Integer.toString(b1), true);
                    }

                    //televic
                    while ((b2 = inCom2.read()) != -1) {

                        //send trough to com2
                        Com1Sender.send(new byte[]{(byte) b2});

                        Main.addText(Integer.toString(b2), false);

                        MessageExtractor.add(b2);

                    }

                    // wait 10ms when stream is broken and check again
                    sleep(10);
                }
            } catch (Exception e) {
                Main.addError(e.getMessage());
            }
        }
    }

this is one of the senders: public class Com1Sender {

        static OutputStream out;

        public static void setWriterStream(OutputStream out) {
            Com1Sender.out = out;
        }

        public static void send(byte[] bytes) {
            try {
                // sending through serial port is simply writing into OutputStream
                out.write(bytes);
                out.flush();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        public static void send(int letter) {
            try {
                Main.addText(Character.toString((char)letter), false);

                // sending through serial port is simply writing into OutputStream
                out.write(new byte[]{(byte)letter});
                out.flush();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

Answer 1

i can't find what the problem is

so i'm going to try it with a physical cable

http://www.commfront.com/RS232_Protocol_Analyzer_Monitor/RS232_Spy_Monitor_Cable_Half_Duplex.htm

or if you're handy:

http://www.lammertbies.nl/comm/cable/RS-232-spy-monitor.html