Hello,
I'm currently working on driving displays in DSI video mode.
The display i'm driving has the following parameters:
xres :480 yres:800
hfp :48 vfp :3
hsw :32 vsw :4
hbp :80 vbp :7
Using RGB888, 2 data lanes, refresh rate of 60 and a sys_clk of 19.2MHz
I succeeded in driving this display however I had an issue of the RGB data on the DSI bus being completely black.
After quite a long time of searching i finally managed to figure out the problem.
The problem was caused by the settings for the clock dividers M4REG+1, LCD and PCD.
CLKIN2DDR =374.4MHz
LCDx_PCLK = 31.2MHz
Total divide needs to be 12
When I set these values to (M4REG+1)12, (LCD)1 and (PCD)1. The issue was present..
When i set them to (M4REG+1)3, (LCD)1 and (PCD)4 the display booted successfully.
The problem is that i do not completely understand the relation between these dividers and how they are calculated individually. The technical reference manual is unclear about these 3 except that their total needs to be correct.
Could anyone explain to me how these values are determined?
Any help would be greatly appreciated.