Establish autoconnection with the scanner

[PEER23PEER]

The code below should establish an auto connection.
It cycles through all available serial comms and sees if it gets an connection and sends a handshake to see if it is the david laserscanner

the code for the PC
the constructor for SYNC.dll

        public SYNC()
        {
            foreach (string PN in System.IO.Ports.SerialPort.GetPortNames())
            {
                try
                {
                    _sp = new SerialPort(PN, 115200, Parity.None, 8, StopBits.One);
                    _sp.Open();
                    if (_sp.IsOpen == true)
                    {
                        _sp.WriteLine("ENTERSYNCMODE");
                        System.Threading.Thread.Sleep(100);
                        string davidHandshake;
                        if (_sp.BytesToRead > 0)
                        {
                            davidHandshake = _sp.ReadTo("!");
                            if (davidHandshake == "13\r\nENTERSYNCMODE")
                            {
                                break;
                            }
                        }
                        else
                        {
                            _sp.Close();
                        }
                    }
                }
                catch
                {
                    _sp.Close();
                }

            }
            if (_sp.IsOpen)
            {
                _sp.DiscardNull = false;
                _sp.DataReceived += new SerialDataReceivedEventHandler(_sp_DataReceived);
            }
            else
            {
                this.noConnectionEstablished(this, new EventArgs()); 
            }
        }

the code for the arduino in the main loop

    if (Serial.available() > 12)
    {
        Serial.println(Serial.available());
        Serial.println("ENTERSYNCMODE!");
        Serial.flush();
    }

[PEER23PEER]

Rewrote the code for the constructor and the handshake routine

Constructor

        public Sync()
        {
            foreach (string portName in SerialPort.GetPortNames())
            {
                try
                {
                    _sp = new SerialPort(portName, 115200, Parity.None, 8, StopBits.One);
                    _sp.Open();
                }
                catch
                {
                    _sp.Close();
                    _sp.Dispose();
                }

                try
                {
                    if (_sp.IsOpen && _handShake()) { break; } 
                    else 
                    { 
                        _sp.Close();
                        _sp.Dispose();
                    }
                }
            }
            if (!_sp.IsOpen) { throw new ArgumentException("No Davidscanner connected"); }
            if (_sp.IsOpen && !_inSync) { throw new ArgumentException("Could not enter SYNCMODE"); }
        }

Private _handShake method

        private bool _handShake()
        {
            bool handshakeEstablished = false;
            _sp.ReceivedBytesThreshold = 14;
            try
            {
                _sp.WriteLine("ENTERSYNCMODE");
                System.Threading.Thread.Sleep(100);
                string davidHandshake;
                if (_sp.BytesToRead > 0)
                {
                    davidHandshake = _sp.ReadTo("!");
                    if (davidHandshake == "ENTERSYNCMODE") { handshakeEstablished = true; }
                }
            }
            catch (ArgumentException)
            {
                throw new ArgumentException("Could not enter SYNCMODE");
            }
            _inSync = handshakeEstablished;
            _sp.ReceivedBytesThreshold = 8;
            return handshakeEstablished;
        }

Arduino Code Main loop

    if (Serial.available() > 12)
    {
        Serial.println("ENTERSYNCMODE!");
        Serial.flush();
        delay(10);
        control.blink(syncBlink);
        SyncMode();
    }

Arduino Code SYNC.cpp

byte SYNC::Recieve()
{
    control.blink();
    delay(10);

    if (Serial.available() > 7)
    {
        byte counter = 8;
        byte incommingBlock[8];

        for (int i = 0; i < counter; i++)
        {
            incommingBlock[i] = Serial.read();
        }

        Serial.flush();

        if (incommingBlock[0] == 2 && incommingBlock[7] == 3)
        {
            switch (incommingBlock[1])
            {
            case 0:     //Command
                break;
            case 1:     // Char

                break;
            case 2:     // Byte

                break;
            case 3:     // Int

                break;
            case 4:     // Long
                break;
            case 5:     // GetSettings
                Send('C', incommingBlock[2]);
                break;
            case 6:
                    isFinished = true;
                break;
            }

        }
    }

    return 0; 
}