LCD flickering/dropped frames LCC PIC32MZ1024EFE
I've posted here a few times with a project I'm working on. We have a PIC32MZ1024EFE design driving a controllerless LCD via DMA & PMP. I'm not using harmony, I pretty much wrote my own as I didn't want to use microchip library code.
We had to make some changes to the design and now have the PCBs in but I've found the LCD has developed an issue. It seems to be dropping frames and flickering! Checking the signals, my frame rate is bang on 62.5Hz and this hardly moves around so I don't think it is software related. The DMA handler has the highest priority
Please see video (it doesn't capture it amazingly well but you get the idea, random lines and screen ghosting? Mostly in 2nd half of vid):https://drive.google.com/...EtSjA/view?usp=sharing
Could this be EMC interference of any kind? We moved some things around on the PCB but tried to keep the LCD tracks short, the 16 colour data lines going to the LCD have 10R resistors to help reduce emissions but these were on our older design which didn't flicker at all.
The other thing my colleague suggested was supply issues, I've had a scope on the 3v3 rail and it doesn't seem to be moving around but I'll keep investigating
Just wondered if anyone had seen something similar with controllerless LCDs and PIC32!