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Problems Getting Started


#1

Hi,

Just unwrapped our new FEZ Cobra with 7" TFT display. I created a new FEZ Cobra Console Application in Visual Studio, successfully built/deployed it, saw the LED blinking and everything was great.

The next step I took was to create a new FEZ Cobra Window Application. After creating the solution in Visual Studio, I copied/pasted the example code from the Cobra brochure, and built/deployed the code. Then I disconnected the Cobra from USB, connected the TFT display, and re-powered the Cobra (via USB).

I’m now stuck in some state where I can’t run, can’t redeploy new code, and can’t access the boot loader. When the board/display start up, I see the GHI logo, along with some boot info in the upper right corner of the display. It remains on the display for a second, then I very briefly see what looks like “Starting” (sometimes I don’t see all of the word), and it resets and starts this process again.

If I try starting up with the boot loader, Windows sees the board and adds it as a new Port (COM7), but it has a little warning icon, and the device status states, “This device cannot start. (Code 10)”. That’s as far as I get.

Any ideas?

Thanks,
Paul


#2

Try to power Cobra from external supply (not USB).


#3

Yes the 7" display is power hungry. You will need a 7.5V power pack.


#4

I’ve got a 6V wall transformer I’ve been using. When I try using it, I see the same behavior with the resets.


#5

Disconnect the 7" display panel. does it work again?


#6

Ok, dumb question #1 for me today. What do you mean when you say “power pack” ?


#7

If I unplug the display, I see the same results.

I can see the board showing up in Windows Device Manager as " Debuggable .Net Micro Framework Device". It gets added and removed from the device list as the board resets.


#8

Also if you can… Ditch the on board 5v regulator and power the 5v rail directly from a good switched mode supply.

Cheers Ian


#9

peddy,

[quote]I can see the board showing up in Windows Device Manager as " Debuggable .Net Micro Framework Device". It gets added and removed from the device list as the board resets.
[/quote]

This is a bit not clear for me. Is the board resetting by itself? or you are pressing the rest button?
The device disappears from the device manager list when it is in reset state, that is normal.

Forget about the 7" display for now, we are talking FEZ Cobra board only, Can you please explain again what the problem is?


#10

Ok, right now, I have the display disconnected.

If I power up the Cobra board (either using USB, or 6V wall transformer),
the board appears to power up, and after a 4-5 second delay, I see the device show up in Windows Device manager.

Then, completely on its own (I’m not touching anything), the entry in the device list disappears, and then reappears another 4-5 seconds later. I have been assuming this is because the board is resetting by itself.


#11

If it’s of any value, I also hear a slight click that coincides with the device disappearing from the Device Manager list. (Maybe the piezo giving brief blip during reset ? ? ? )


#12

When you connected the 7" display. Were you sure that it was connected in the correct orientation?

Do you notice that the EMX module, 3.3V regulator, 5.0 Regulator are getting extremely hot?


#13

Yes, I’m assuming the display was connected correctly if I was able to see the GHI logo and boot text in the upper right corner of the display.

I’ve been monitoring all the regulator temperatures (with my very non-scientific method of using my fingers as a temperature probe), and haven’t noticed anything more than “warm”. It’s not been hot. I could leave my finger on it indefinitely without becoming uncomfortable.


#14

[quote]Yes, I’m assuming the display was connected correctly if I was able to see the GHI logo and boot text in the upper right corner of the display.
[/quote]
Very good. I donlt see that you have a hardware issue.

Can you measure the 3.3 Voltage on the board?

Can you Erase the application using MFDeploy? I am afraid that the application deployed has a Restart() method.

Or better access GHI boot loader and erase everything, then reload the tinybooter and the firmware.


#15

More information that might be useful:

I just reattached the display. The board/display went through about 8-9 resets where I’d see the GHI logo, then the " Starting " text, then a reset (the resets happened by itself).

After the 10th or so reset (I wasn’t keeping an accurate count), it stopped resetting, and the display started “fading”. It’s kind of hard to describe. I could still see the GHI logo on the display, but the background (black) pixels starting to illuminate, causing the image to fade.

Also, at this point, the the regulators on the board (IC1, IC2) were very warm, and I unplugged it. Previously, I hadn’t left it running that long.


#16

the configuration code does have reboot method

// Set config
            if (Configuration.LCD.Set(lcdConfig))
            {
                // New settings were saved, must reboot
                Microsoft.SPOT.Hardware.PowerState.RebootDevice(false);
            }


#17

Ok… progress.

I tried using the bootloader/MFDeploy to erase the device. It took a few tries (the EMX_EMX value in the dropdown kept appearing/disappearing as the board was resetting by itself). After a few attempts, it managed to erase, and now I’m not seeing the reset problem.

I loaded the blinking LED console application, and things are running again.

So my next question is, what happened?


#18

Oh crap… I think I see what I did. In the process of copying/pasting the example code, I must have gotten messed up at the page break in the brochure for the 7" display. I ended up pasting this:

if (Configuration.LCD.Set(lcdConfig))
{
   // New settings were saved, must reboot
   Microsoft.SPOT.Hardware.PowerState.RebootDevice(false);
}
// New settings were saved, must reboot
Microsoft.SPOT.Hardware.PowerState.RebootDevice(false);

So RebootDevice was getting called every time. Ack. Is it Friday yet?

Thanks for the help.


#19

I do have same problems with my 7" display. Gonna return both Fez Cobra and the 7" money sucker to GHI for refund. Will stick to FEZ Domino - I love it!


#20

[quote]I do have same problems with my 7" display. Gonna return both Fez Cobra and the 7" money sucker to GHI for refund. Will stick to FEZ Domino - I love it!
[/quote]

If you noticed in the last post. peddy’s problem was a copy-paste mistake that he made. the FEZ Cobra nad the 7" display are just fine. :wink:

If you have a different problem please tell us.