800 x 800 Display with STM32U5G9VJT6Q - possible?

[Ricko]

Hi,

we are trying to get a 800x800 display to work with the STM32U5G9VJT6Q, using either RGB888 or RGB565 in Video Mode (Burst).

According to what we read it is definitely possible. Did we miss something?

Could someone please confirm that is definitely possible?

Much appreciated

Thank you

[Ricko]

Thank you @Tesla DeLorean 

I have that controller datasheet but it does not show any clock specs.

The manufacturer suggested the pixel clock = 44MHz (which is what we also get) and the DSI clock = 270MHz so byte clock = 33.75 MHz

But CubeMX does not allow setting the PLL to that combination of values, which is the reason for asking the previous question.

For example, if I set the the pixel clock to 44MHz (as suggested by the manufacturer) then the values that CubeMX calculates for the DSI are only 33 MHz (lower than the minimum so not an option) or 44 MHz (quite a bit higher than the value suggested by the manufacturer).

That is why I was asking whether I can set the DSI much higher than the minimum value of 33.75MHz (in this case 44MHz)?

Thank you :)

[MM..1]

Try show screenshot , where CubeMX calculate 33MHz for DSI? And display info is clasic defined for 4 lanes MCUs.

Then for STM you require 33,75x2, but this is over 500 limit... Simply start test display on max DSI speed 62,5MHz byte DSI clock. Display controllers accept this speed , but require right setup for LP iddle transitions etc.

[RobNewbury]

Hi Ricko,

Did you get your display working? I'm having similar problems with a Tailor Pixels display (TTH040BRT-02C) which also uses JD9365DA-H3. I am sure I have the timings correct but the display remains blank.

I know that LP commands are being processed correctly as I am enabling the TE output to check the frame timing and this is correct. I've also used the LP command to activate the display built in self test which works, but oddly only if the D-PHY bus is stopped, the JD98365 datasheet is poor so this may just be how it's supposed to operate. 

I'm using STM32F469 and have taken into account the maximum supported pixel frequency as per AN4861 and discussed earlier in this post.

I have been succesful using Tailor Pixels TTH345BRS display, but this uses FL7705 controller.

Do let us know how you got on with driving your display. :)