通过C＃接收RS485命令

Question

I have been googling and haven't found any code to help me with this, maybe I missed something? I want to receive RS485 commands. At the moment I am just receiving rubbish. Here is my current code although I don't think it would help:

//C# CODE
byte[] arr = new byte[serialPort1.BytesToRead];
serialPort1.Read(arr, 0, serialPort1.BytesToRead);
String s = "";
foreach (byte b in arr)
{
     s += b.ToString() + " ";
}
/*String s = serialPort1.ReadByte().ToString();
while (serialPort1.BytesToRead > 0)
{
     s += " " + serialPort1.ReadByte().ToString();
     Thread.Sleep(10);
}*/
//String s = serialPort1.ReadLine().ToString();
richTextBox1.Invoke((MethodInvoker)delegate { richTextBox1.AppendText(s + "\n"); });

This was just a test to see if I could receive the data. Does anyone know how I can receive data through serial port and show them in a text box?

Answer 1

I am not sure about your final goal but if you are looking only to receive data and show them in a text box, there should be no difference with a standard RS232 serial communication, this should do it. The name of the text box in this example is txtOutput.

To start:

  public Form1()
    {
        InitializeComponent();

        serialPort1.PortName=("COM1");
        serialPort1.DataReceived += new System.IO.Ports.SerialDataReceivedEventHandler(serialPort1_DataReceived);
        serialPort1.Open();
    }

serial port

  private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
        {

            try
            {
                SetText(serialPort1.ReadLine());

            }

            catch (Exception ex)
            {
                SetText(ex.ToString());
            }

        }

Delegate:

delegate void SetTextCallback(string text);

Append to text box:

 private void SetText(string text)
        {
            if (this.txtOutput.InvokeRequired)
            {
             SetTextCallback d = new SetTextCallback(SetText);
             this.BeginInvoke(d, new object[] { text });
            }
            else
            {
                txtOutput.AppendText(text + "\r\n");
            }}

Remember to set the serial port1 with bauds and make sure you have added the serial port to your form. I have tested the code with a standard serial connection and it is working.