cannot read the data from arduino to the c#

Using Arduino Interfacing w/ Software on the Computer
28

Let me make sure I understand correctly.

  1. Your Arduino is running code outputting data to serial port.
  2. You want the data Arduino is sending to serial port to be read into your C# program and displayed on a Windows Form.

I think you have your read and write backwards. You aren't trying to WRITE the output from serial to your C# GUI, you want to READ the output from Arduino, into your C# program and then display it in the GUI.

set a string variable in C# = sp1.readline()

Then set the GUI element ".TEXT" field = to the string variable you created to display it.