Arduino无法从串行读取？

Question

I'm working on some bluetooth-based arduino to c# (on computer) communication. A lot of the code I've been using was taken from examples, but here's the current situation.

When I send messages from my arduino to my computer, by writing to serial, they show up--I generally need to include a newline character, but that's not a big deal.

However, when I send messages to my arduino, it never even acknowledges that it got them. Any ideas on why this might be? Here's the relevant code.

(Note, I'm using an Arduino uno, and a basic serial bluetooth modem).

char inChar; // Where to store the character read

void setup()
{
   Serial.begin(9600);  
}

void loop()
{
  if (Serial.available() > 0)
  {
      inChar = Serial.read();
      Serial.write("processing message...\n");
  }
}

Nothing is ever written to serial in this program, indicating that it never sees that it has stuff to read.

EDIT: Forgot to post the C# code. Whoops.

    string message;
    StringComparer stringComparer = StringComparer.OrdinalIgnoreCase;
    Thread readThread = new Thread(Read);

    // Create a new SerialPort object with default settings.
    _serialPort = new SerialPort();

    // Allow the user to set the appropriate properties.
    _serialPort.PortName = SetPortName(_serialPort.PortName);
    _serialPort.BaudRate = SetPortBaudRate(_serialPort.BaudRate);
    _serialPort.Parity = SetPortParity(_serialPort.Parity);
    _serialPort.DataBits = SetPortDataBits(_serialPort.DataBits);
    _serialPort.StopBits = SetPortStopBits(_serialPort.StopBits);
    _serialPort.Handshake = SetPortHandshake(_serialPort.Handshake);

    // Set the read/write timeouts
    _serialPort.ReadTimeout = 500;
    _serialPort.WriteTimeout = 500;

    _serialPort.Open();
    _continue = true;
    readThread.Start();


    Console.WriteLine("Type QUIT to exit");

    while (_continue)
    {
        message = Console.ReadLine();

        if (stringComparer.Equals("quit", message))
        {
            _continue = false;
        }
        else
        {
            _serialPort.WriteLine(
                String.Format(message));
        }
    }

    readThread.Join();
    _serialPort.Close();
}

Answer 1

The arduino code as it is will only read one byte from serial and continue the flow. You might want to replace your if statement with a while statement like so:

while (Serial.available() > 0)
  {
      inChar[i] = Serial.read();
      i++;
  }
Serial.write("processing message...\n");

This will put the received message in a char array. (You'd also need to declare inChar as an array eg - char inChar[8]; )

Other than that it should work unless there is something wrong with your C# code which I can't test right now but it looks fine.

Hope this helps.