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I've been having a look at the problem you've described (since I've been working on some serial port things myself).
First, I'm assuming you've got D0 (COM1 Rx) connected to D3 (COM2 Tx), and D1 (COM1 Tx) connected to D2 (COM2 Rx) here.
Given that, if you look in the SerialPortHelper.cs class, the serialPort variable is declared as static (as are buffer and
bufferlength). I think what's happening is that since you've instantiated two separate ports in your class, you're actually sharing
resources between them. So when an event is fired to say "data has been written to COM1", the code reacts to that event
by trying to read from COM2. If you leave the serialPort variable as static, and change the serialPort_DataReceived
method to look like the code below, you'll see what i mean:
private void serialPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
// i expect these to both return the same port
// if serial port is static, i find they're different.
Debug.Print("serial port name = " + serialPort.PortName);
Debug.Print("sender name = " + ((SerialPort)sender).PortName);
lock (buffer)
{
if (serialPort.BytesToRead > 0)
{
int bytesReceived = serialPort.Read(buffer, bufferLength, bufferMax - bufferLength);
if (bytesReceived > 0)
{
bufferLength += bytesReceived;
if (bufferLength >= bufferMax)
throw new ApplicationException("Buffer Overflow. Send shorter lines, or increase lineBufferMax.");
}
}
}
}
So basically I think if you use the method above, and remove the static modifier from the serialPort variable, you
should make some progress. You might want to remove static from the other two member variables too.
I guess you'll also have noticed I added a little bit to that code to check if there's at least one byte to read from serialPort.
Stepping through your program slowly in debug mode gives me different behaviour to when I just run it
without breakpoints - I found there was an exception in this method because whereas we've been notified that data has
been received, when I actually look at the serialPort.BytesToRead property I find that there's nothing there. I couldn't
work out why the event was being fired, if you have an answer I would be really interested to know!
But this looks like a great library, it's interesting to me as well.
I hope this helps - let me know how it works out.
Jeremy
Thanks again,
Jeremy
But I hope this is something to look into anyway!
Cheers,
Jeremy
