Diagnose if Cobra dead


I’ve had a Fez Cobra + RS21 module running for about a month non stop, however today noticed it was no longer working. I’ve tried to connect to it via MFDeploy, but I just get the error ‘Connecting to …Failure - Device is invalid or not responding’.

I know my program is not executing on it either as IO48 is partially on, where as I turn it off on startup. The lights on the board that are on are:

  • Ethernet (orange)
  • IO48 (Half on - like when in the undefined state, neither high nor low).

No LEDs on the RS21 module are on.

Is there a way to check it any further, or is it on an express trip to the bin? I don’t see why it should have failed though, nothing changed for a month…

hey Ross,

mmm, strange and bad news.

So here’s what you should do. Disconnect as much as possible from the board, and then connect it to a PC. Looking in Device Manager, what is showing up. In particular you’re looking for the .Net debuggable device. If that isn’t showing up, I’d try resetting it and going into bootloader doing the magic button press, then you should see the serial port show up.

Phew - thanks Brett!!

It didn’t come up in device manager to start with, but gave it the magic buttons and managed to re-flash the cobra. Then deployed app to it OK again.

I don’t know what happened to it, but its back in the living world again now! =)

great news Ross and glad to have helped out