Write a multiple sensor command and read simontenously

Question

I am new to C # and am trying to develop a draft window shape for the RS-485 water pressure sensor. From my code, when I write only one sensor command and read, it works correctly. But when I write the whole command and try to execute it, it does not work correctly. In my code, DatafromCOM is a global variable with a string value, and in Timer I wrote code for the write sensor command. Can you give me some solution for this, I try to do it in one week, and I can not find a solution for this. My code is below

 private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
 {
     while (serialPort1.BytesToRead != 0)
     {
         DatafromCOM = serialPort1.ReadLine();
     } 
}

private void timer1_Tick(object sender, EventArgs e)
{ 
     string cmdCurrent = "D0107012A0C";
     string cmdCrntTW = "D0107022B4C";
     string cmdVer = "D010703EB8D";
     string cmdConf = "D01070429CC";
     string cmdAdd = "D010705E90D";
     string cmdCorr = "D020B10";
     string cmdAvg = "D011011";
     string cmdLvlCor = "D010B12";
     string cmdGrvty = "D010B14";

     serialPort1.Write(cmdCrntTW + NewLine);
     serialPort1.Write(cmdVer + NewLine);
     serialPort1.Write(cmdConf + NewLine);
     serialPort1.Write(cmdAdd + NewLine);
     serialPort1.Write(cmdCorr + NewLine);
     serialPort1.Write(cmdCorr + NewLine);
     serialPort1.Write(cmdAvg + NewLine);
     serialPort1.Write(cmdAvg + NewLine);
     serialPort1.Write(cmdLvlCor + NewLine);
     serialPort1.Write(cmdGrvty + NewLine);

     txtKQ.Text += DatafromCOM + Environment.NewLine;
 }

Answer 1

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