emWin Library Pixel format issue

Miren · Sep 4th 2023, 3:06pm

We are using a STM32H745 microcontroller interface with 1280 x800 TFT lvds display.

RGB data from controller LTDC data convert through SN75LVDS83 IC and LVDS data fed to tft display.

we are facing a issue in pixel format which is not update in 0 degree rotation with ARGB8888 color format.

also we observe that 180 degree rotation with ARGB8888 format , we got clear resolution and no any corrupted pixel shown.

we are using STemWin graphics library.

Please suggest 0 degree rotation format with ARGB8888 color format.

Please find the attached screen image.

SEGGER - Florian · Sep 5th 2023, 10:13am

Hi,

This looks like the data cache is not cleared before a DMA2D (ChromeArt accelerator) operation. The DMA2D is disabled for rotated configurations, therefore this should only occur when the display rotation is disabled.

Could you please send me your LCDConf.c?

Thanks and best regards,
Florian

Miren · Sep 5th 2023, 2:19pm

Hello Florian,

Thanks for the quick reply.

Please find the attached zip file which contains LCDConf.c and LCDConf.h file.

SEGGER - Florian · Sep 6th 2023, 2:55pm

Hi Miren,

In your LCDConf.c in line 1039 call to GUI_DCACHE_SetClearCacheHook() is commented out. You would have to set this hook function so that the data cache will be cleared.

Then, you need also need to add a call to GUI_DCACHE_Clear() at the beginning of _DMA_ExecOperation(). This should prevent the artifacts that you are seeing on your screen.

Best regards,
Florian

emWin Library Pixel format issue

emWin Library Pixel format issue

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