Dingoo A320 forum

My Dingoo exhibits diagonal tearing. This is easily visible in some of the example videos and in lots of NES games that make the screen flash, like Megaman for example.

The GP32 WIZ has a similar problem: they used a LCD screen intended for portrait orientation in landscape mode and the screen is simply not fast enough in this drawing mode. For a general explanation what tearing is, see this:
http://hifi-india.blogspot.com/2006/11/ ... -do-i.html

It's like that only diagonal.

Did anyone else notice this or is it only my Dingoo that does this?

Yes, I see this. I am hoping that a different technique to update the screen will help. The diagonal tearing makes me think that pixels are being updated left to right, top to bottom. Perhaps if a double buffering technique were used, where the screen VRAM pointer were switched and therefore change the entire screen at once, and synchronize this switch to a screen refresh interrupt, this would alleviate this problem. But it may be a property of the hardware itself.

Another one has it problem on his black Dingoo?

My Dingoo exhibits the same behaviour. I had figured it was due to the reasons mentioned, or at least to the LCD controller itself being odd.
I imagine this is why we see the glitching in the Genesis/MD emulator. It's possible that the emu is writing to the screen too quickly for the controller to handle during fast motion (BLAST PROCESSING RULES THE SKIES )

I can confirm this on the black dingoo. There has been discussion on this over on the openhandhelds forums. Exhophase (the developer behind gpsp) chimed in on the subject because the wiz was having the same problem and the cause is likely the same: the screens are meant to be used in portrait mode, but are being used in landscape mode. This situation could be fixed in software like the wiz, but it may very well effect program performance (due to using processing power).