title: Winform SerialPort can't firing DataReceived
body: <pre><code>public partial class Form1 : Form
      {
          public Form1()
          {
              InitializeComponent();
              serialPort1.Open();
              serialPort1.DataReceived += new SerialDataReceivedEventHandler(SerialPort1_DataReceived);
              serialPort1.Write("test");
          }
  
          private void SerialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
          {
              //cant firing event
          }
      }
  </code></pre>
  
  <p>i already write some string to serialport but cant's firing DataReceived event??
  <img src="https://i.stack.imgur.com/TwrLy.png" alt="my serialport setting"></p>