7" CPLD with Arduino Due and UTFT screen refresh issue


I have a 7" CPLD display with the MD070SD. This display works perfectly on a Mega2560 with the CTE shield and the UTFT library. I am trying to get the display to work with a Due and the corresponding CTE shield. I guess it technically does work, but when I run the 800x480 UTFT demo program it never writes cleanly. In particular it doesn't seem to completely clear the screen or write a color over the entire screen cleanly, it instead leaves behind "ghosts" of the previously displayed image or shape. When it is used with the Mega it runs perfectly, albeit slowly.

I have uncommented line 4 in the HW_ARM_defines.h


and I am calling out the constructor like this

UTFT myGLCD(CTE70CPLD,25,26,27,28);

Now, my first suspicion was that the CTE Due specific shield had some sort of issue, but when I bought another the issue persisted. I then thought that there was an issue with the Due, so I bought another one of those and the issue still persisted. I am using an external power supply, not just the USB connection through the Due.

I'm kind of a noob as you can tell, so I'm sure I'm missing something very simple here. The UTFT demo runs and completes, it just doesn't display the images cleanly. Any help would be greatly appreciated!


It is a little disappointing you are having issues with a CTE display, personally I don’t have access to a 7" CPLD display but I do have a 5" CPLD, and I have no issues whatsoever.

Could you post some pictures?