I'd guess that the Main loop is spinning, preventing the event from firing.  Add a Thread.Sleep(10) in your Main while (true) loop to give the event queue a little breathing room.

The .NET event is similar to the Arduino interrupt, the big difference is the event is queued and processed in the same thread as the event source and interrupts are much more immediate.  Since the _port is running in the main thread, the light loop in Main isn't yielding to let the event fire.

I haven't done this myself, but you could use one of these:http://www.ghielectr...log/product/405 to break out the pins from the GO socket to the pins on the relay board.

I've had great success with the SainSmart relay boards using Netduino+, haven't tried them with the GO.

Just to close the loop, using a few RS232 Shifters (SparkFun PRT-00449) and the Netduino Plus 1, I was able to communicate at 19200 7E2.  Unfortunately, after all of this, the barcode scanner doesn't support the UCCEAN128 barcode format required for the DHL label we needed to use.  After all of that, the project was scrapped.

The good news is that we have identified a few other places on our manufacturing floor where the Netduino platform can be used,

The scanner is an old AccuSort Mini-X, I'm pretty sure I can change the data line to 8N1.  If I can't, I have a few Netduino 1s on my desk at home, I'll grab one of those. 

I really can't thank y'all enough.  Evey time I've had a problem and posted a question, I've had a helpful response far quicker than I expect.

Specs for the barcode scanner said 5V, but meter says 12V a few minutes ago. Hmph. I only need to validate the receive bit tomorrow, I'll whip up a voltage divider until I can get a proper level converter.  If it was a simple voltage problem, this should take care of it.

I'll hold off on updating the firmware, last time I did that it didn't work out quite so well.

Having trouble reading 19200, 7E2 data from COM2 and COM3 with Netduino Plus 2.

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After playing with Netduinos at home, I finally brought one in to work for a relatively simple project.  The board is the Netduino Plus 2 RevA with stock firmware.  The Netduino should sit in the middle of an RS232 connection, reading values from one SerialPort, converting the data, then sending it out the other SerialPort.  The problem seems to be the port configuration that I have to use.  It's 19200, 7E2.  I read in another forum topic here that COM1 may have problems with anything other than 8N1, so I'm using COM2 and COM3.  Everything initializes correctly, no exceptions creating or opening the ports.  The data that is read looks like regular garbage data that you'd see with a config mismatch.  Connecting the input to a Windows XP Hyperterminal session with 19200 7E2 gives me good valid reads.  It sure looks like the Netduino is having trouble with this configuration.

The setup is pretty straight forward, an overhead barcode scanner sends data through RS232, RS232 connected to Netduino COM2 pins, DataReceived handler writes to SerialLCD on COM1 and log file on SD card.  Once receive is OK from COM2, send the modified data out COM3 at the same config.

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