C#

private void btnStart_Click(object sender, EventArgs e)
        {
             //Makes sure serial port is open before trying to write
            try
            {
                if (!sp1.IsOpen)
                    sp1.Open();

                sp1.Write("*X01\r");

            }
            catch (Exception ex)
            {
                MessageBox.Show("Error opening/writing to serial port :: " + ex.Message, "Error!");
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // all of the options for a serial device
            // can be sent through the constructor of the SerialPort class
            // PortName = "COM1", Baud Rate = 9600, Parity = odd, 
            // Data Bits = 7, Stop Bits = One, Handshake = None
            sp1 = new SerialPort("COM1", 9600, Parity.Odd, 7, StopBits.One);
            sp1.Handshake = Handshake.None;
            sp1.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived);
            sp1.ReadTimeout = 500;
            sp1.WriteTimeout = 500;
            sp1.Open();
        }

        void sp_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            Thread.Sleep(100);
            string data = sp1.ReadExisting();
            this.BeginInvoke(new SetTextDeleg(si_DataReceived), new object[] { data });
        }

        private void si_DataReceived(string data)
        {
            char[] charsToTrim = {'X','0','1'};
            textBox1.Text = data.TrimStart(charsToTrim);
            
        }

mprice214 wrote:

enabled

Stopwatch ObjStopWatch = new Stopwatch();
           ObjStopWatch.Start();
           long StDelay = ObjStopWatch.ElapsedMilliseconds;
           try
           {
               string FromModem = "";
               Comport.ClearInputBuffer();
               Comport.Write(Command);
               Comport.Write(new byte[] { 0x0D, 0x0A });
               do
               {
                   if (Comport.InBufferCount>0)
                   {
                       Comport.Read(Comport.InBufferCount);
                       FromModem += Comport.InputStreamString;
                       if (FromModem.Contains("OK"))
                           break;
                   }
               } while ((StDelay + 5000) > ObjStopWatch.ElapsedMilliseconds);

private void DisplayText(object sender, EventArgs e)
{

    textBox1.Text = RxString;
    serialPort1.DiscardInBuffer();
    while (serialPort1.BytesToRead == 0)

        serialPort1.WriteLine("*X01\r");


}

private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
    RxString = "";


    try
    {
        RxString = serialPort1.ReadTo("\r");

    }
    catch (Exception Exception)
    {
        return;
    }

    this.Invoke(new EventHandler(DisplayText));
}

private void textBox1_TextChanged(object sender, EventArgs e)
{

}

private void timer1_Tick(object sender, EventArgs e)
{
    //timer1.Interval = 50;
    //if (!serialPort1.IsOpen) return;
    //serialPort1.WriteLine("*X01\r");
}