Pixel computation issue
- June 18, 2019
- 4 replies
- 1460 views
Hi all, I'm running into an issue and I need some ideas!
We have designed a project on a STM32T769 disco board and we are now porting it onto our own hardware that uses an STM32H743 chip. We have 64MB of external SDRAM (two chips of 32MB each running in parallel) and a parallel LCD display. All code runs from internal flash and for this part (the bootloader), all assets of TouchGFX are also in internal flash.
We are seeing weird pixels on our display. I attached an image. Basically, some lines close to the squares are the wrong color. Look at the lower right blue square, it has a black line on the left. The text is also quite blurry. As if some calculations were wrong. I was able to see the these wrong pixels are actually into the frame buffer in SDRAM so it is not a LCD timing issue.
It seems to be related to computations made for overlapping objects as if I only have one color box, I see no issues.
Any body has ideas on what to look for when facing this kind of problem?
Thanks in advance.
