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Cobra 2 need reflash firmware after power off/on


#1

Hi All! I’m use FEZ Cobra 2 for home automation and all works fine.
But sometimes when power on board is off and on, or i update the program on it, the program does not start and Cobra 2 stop responding to pc by usb. Helps only firmware reflash. But after a while (power off and on) all repeats. And this happens on both FEZ Cobra 2 boards, so defects are excluded.
It does not happen very often, but I would like to find out what the problem is

Please Help.


#2

It might be your application.

If under some special conditions your app uses 100% system resources
like an

while(true)
{
   // empty loop
}

Then the debugger can not connect to your device anymore (or only by luck).


#3

The workaround for above situation is to start deploy and the right away reset the board.
VS will connect before the app is running and deploy normally.


#4

All this is true, but strange that pc not even defines it as a device, reporting that usb device is not recognized. Seem that boot loader in g120 not started … Can this happen due power surges ?


#5

@ alwin - What do you mean by boot loader?


#6

If boot up time is not critical then add Thread.Sleep(5000) as the first line of code. That garentees you a bit of time for the debugger to connect. Also you can hold down reset, click build in VS then release reset. This seems to work for me.


#7

Boot loader i mean, code on controller that give PC to determine usb controller device. I think that controller stuck before program execution and not response to PC, reconnection not help me, only reflash solve this problem. I don’t know technically how this is work but sometimes controller after reflash program refuses to be determined by PC.
PS. Sorry for my bad english


#8

Thanks for the advice I’ll try do it.