Newbie problem with Cobra and 7

hi guys

I am having some startup problems. When i start my module the display cycles through different colors. For a brief second it shows GHI logo and firmware status then jumps back to changing colors.

I have tried to use the example from the display. It compiles fine after removing error in font lines and then deploys without error. All i see on screen is chaning colors… bought 3 units and all does the same.

If i deploy graphical_demo to the board i can hear that it responds to touches on the screen but it is still just changing colors…

Thanks in advance for replys i am so eager to play with my new toys.


Have you upgraded the firmware & ghi .Net libraries to the latest version?

Yes runnning on the newest firmware and code.

Update Cobra once more using Tera Term and the firmware file available in SDK directory. Than I suggest you try this: open VS2010, create new project using Cobra template, deploy to device. Let us know if the effect still occurs.

Is this the 7" display?
Have you tried to use powered hub or tried adding power to the board instead of relying on USB power?

Hi guys

Thanks for the fast replys.

I have 2 identical setups one where i have unpacked a Fez Cobra and a 7" display where the cobra fits on the back. Both is running on 6V powersupply and i have checked that the power is steady at 6V.

This problem is straight from i unpack it, and attach the LCD cable and power on.

One i have firmware updated by using the great youtube guides. and then tried to load the graphical_demo in to it. I can hear that the touch responds to touch (Think i start a game) but the colors are still changing.
It looks like it is some kind of “screensaver” build in to the display. It goes from green -> red -> white -> B/W large checker -> b/w small checker. The delay between the color change is aprox 1-2 sec. BTW. the GHI logo only shows once on boot.

The color pattern might be a little different color wise it was just to give you an idea what happens. It looks like a program running not a faulty display.

Thanks in advance


Looks like i solved the problem. The USB cable that came with the board was defective… Changes to another one now it seems to work.

Glad it worked for you. Please let us know if there is anything we can do to assist further.

I remember someone else also reporting on forum that USB cable that came with his FEZ was broken.