Image is getting flickered by the handleTick function using TextArea

[Shivani]

In the ScreenView(), Iam adding a handleTick function and trying to update the value for every one second. The value is updating according to the code I have written. But at the time of updation my screen is flickering.

May I know what is the reason?

And I am initializing the external SDRAM peripheral and not configuring the MPU related things.

Thank you.

[Mohammad MORADI ESFAHANIASL]

Hello @Shivani ,
Unfortunately, there can be multiple reasons for this issue and I'm not sure which one it can be. Could you please check if your screen still flickers if you only have your textArea that you update the value for? And are you using an MPU or MCU? Which model are you using?
And is it possible to provide a video or image of the issue?

Thank you

[Shivani]

Hello @Mohammad MORADI ESFAHANIASL ,

Actually, I found that there was no problem with the Text Area, but it is with my SDRAM Initialization in STM32H745I Discovery Board. Without the SDRAM Initialization it is working fine. (i.e. using the internal memories rather than the initializing of the external peripherals). Iam using the MT48LC4M32B2 part number SDRAM in this STM32 Board.

Iam attaching the SDRAM related files that I have used in the SDRAM Initialization in my project. kindly check the files and let me know the reasons of screen flickering.  

Thank You.

[Mohammad MORADI ESFAHANIASL]

Hello again,
There is already a board setup ready for STM32H745I Discovery in the TouchGFX Designer that you can easily use to develop your application, and SDRAM and other required parts are already configured.
STM32H745I Discovery

Is there any specific reason that you are not using this setup?
If you still want to use your own configuration, you can consider this setup as inspiration.

I hope this helps you

[Shivani]

Hello @Mohammad MORADI ESFAHANIASL ,

I need to use my own configuration (i.e  from pin configuration in Stm32cubeMX). I found that with the SDRAM I am getting the Display flickering. Without initializing the SDRAM I can see the screen clearly without flickering. Iam Unable to find the solution to display the screen without any flickering. And I also observed that the flickering is getting more when I tried to change the multiple screens (i.e. screen transition) and updating the values through some TextArea in the Screen.

What are the things I need to change in the SDRAM initialization? I have refered the repository files of STM32H745XI Discovery Board for the SDRAM initialization. 

Thank you..

[Shivani]

And I am using an external display for the STM32H745XI Discovery Board. 

[Mohammad MORADI ESFAHANIASL]

I understand.
I've taken a look at the files you have attached and noticed that you are creating these files yourself. Unfortunately, I'm not an expert on SDRAMS, but I think it would be a better solution to configure the related settings through your STM32CubeMX project.
You can access those settings from Connectivity -> FMC -> SDRAM. 
SDRAM settings in CubeMX

 Please check if this can help you resolving your issue.
Good luck 

[Shivani]

Hii @Mohammad MORADI ESFAHANIASL ,

I have configured from STM32CubeMX and initialized the pins from Connectivity -> FMC -> SDRAM. 

And I also enabling the LTDC, but the screen is getting flickering when I enabled 24bpp in ltdc, and I am not getting any flickering issues when I enabled the 16bpp in ltdc and the external SDRAM.

What is the clock I need to configure for FMC with SDRAM?

Is my screen is getting flickering because of the SDRAM clock issues?

[MM..1 · Accepted solution]

@Shivani happy new year. Your info lacks display resolution. But for any custom good is read LCD-TFT display controller (LTDC) on STM32 MCUs - Application note

For memory config on discovery, try generate TGFX project and extract config SDRAM from it. But important is too clock configs...