using System.IO.Ports;

namespace TextEchoService
{
    class Program
    {
        static void Main(string[] args)
        {
            var serialPort = new SerialPort("COM1", 9600, Parity.Even, 8, StopBits.One);
            serialPort.Open();
            string message = "";
            while (message != "quit")
            {
                message = serialPort.ReadLine();
                serialPort.WriteLine(message);
            }
            serialPort.Close();
        }
    }
}