I have been using a STM32F469i Disco board to interface with a 800x800 LCD in MIPI DSI video burst mode. In order for this to work from the DISCO board, I have an adapter PCB to connect from the DISCO board to the LCD.
It took a while to get going, but the setup with the custom LCD and DISCO board is working fine.
I have recently moved to a custom board; I have intentionally made the video dependent aspects of this board the same as the disco board so that I can run my software on either the disco or the custom board without making any changes.
The custom board sometimes exhibits odd behaviour when rendering from the SDRAM via the LTDC.
Enabling the test colour bars from the DSI always display ok without any problem.
From SDRAM/LTDC, the horizontal start point shifts from the left side of the display to some arbitrary location across the width of the display. This occurs randomly, it can be running for hours and remain stable, other times it may shift once, then be stable for a time and maybe shift again later. It seems to occure more often following a reset, sometimes with repeated horizontal shifts. Once settled it seems to remain settled for long periods. On occasion the LCD will revert to black, however this is the exception rather than the norm.
I have run a memory test and it's not the SDRAM becoming corrupted. I don't rule out FMC timing issues, so I have checked the FMC timing configuration. As I am using the same SDRAM as that on the DISCO board, I wouldn't really expect these timings to be wrong.
Any ideas would be appreciated.
This is the custom board.
This is the DISCO board with LCD interface
