C ++中的串行通信（Visual Studio 2010，.NET 4.5）

Question

I've got a clarification question regarding the receiving of data from across a serial port from an Arduino. Specifically, I'm using a Sparkfun Pro Micro 5v/16MHz and trying to write a simple GUI in C++ to send messages over the serial port and then receive one of a few responses that are specified in the code running on the Arduino board.

I know the communication and code running on the Arduino works because I have tried using the Serial Monitoring tool in the Arduino IDE and am able to send and receive the appropriate responses.

When sending messages through the C++ GUI I've created I see the traffic LED blinking on message send leading me to believe that send via C++ GUI is working, but nothing regarding receiving messages works.

Some of my code:

private: System::Void serialPort1_DataReceived(System::Object^  sender, System::IO::Ports::SerialDataReceivedEventArgs^  e)
        {
            String^ testStr = serialPort1->ReadExisting();
            log_textBox->Text += testStr + "\n";
        }

It's a very simple event handler that is assigned to the DataReceived event of my SerialPort object that is part of my form. I've set a breakpoint inside of it, and it never gets triggered. I'm kind of at a loss, I've done a nonexistent amount of work with Arduino or hardware so I'm not entirely sure what my options are for debugging.

If anyone has any debugging suggestions or ideas what I'm doing wrong I would very much appreciate it. Additionally, if I haven't provided any information let me know what is needed and I'll edit it in!

Thank You, -K

Answer 1

Finally figured this out after finding an obscure comment talking about settings.

It turns out that I needed the DTREnabled property of the Serial Port to be set to True as opposed to false in order for the DataReceived handler to fire. This setting was never set in any of the MSDN documentation regarding Serial Port communication. If you are reading this and are having a similar problem, make sure that DTREnabled, RTSEnabled are both set to true, and perhaps even set Handshaking to RequestToSend. Perhaps one or all of these will be what ends up fixing it.

In my case, only DTREnabled needed to be true. I don't quite understand what these settings do, but there you have it.