This will get the arm working for you.
var serialPort = new SerialPort("COM7", 115200, Parity.None, 8, StopBits.One)
{
DtrEnable = true
};
serialPort.DataReceived += this.DataReceived;
serialPort.Open();
.....
serialPort.Write("G2210 S150 R90 H50 F10000\n");
....
serialPort.Close();
private void DataReceived(object sender, SerialDataReceivedEventArgs e)
{
var local = (SerialPort)sender;
int lengthToRead = local.BytesToRead;
byte[] rxBytes = new byte[lengthToRead];
local.Read(rxBytes, 0, lengthToRead);
var response = Encoding.ASCII.GetString(rxBytes);
....
}
Change “COM7” to whatever COM port your arm is reported as connecting to.