ADC run by DMA & TouchGFX DCache issue

[Emilmart]

Hi,

I have a custom board with STM32H7 & TouchGFX.

I'm using DMA triggered by interrupt to sample datas with my ADC.

Without DCache enable, it's working well. But TouchGFX fails if DCache is disabled (problem meet by others here: https://community.st.com/s/question/0D53W00000S752ySAB/touchgfx-4160-issue-when-dcache-is-disabled )

And if my DCache is enabled, my ADC DMA sampling fails if I move from one screen to an other. (the DMA appears to stop)

I was thinking not using DMA for ADC but it kinds of mess with the generated code.

Any ideas how I can keep both DMA with ADC & TouchGFX running ?

Thanks !

[MM..1]

How type DMA you use circular or restarted by trigger? Same core which one?

I use circular on F4 and dcache without troubles.

[Emilmart]

I use a circular DMA with sampling triggered by rising edge of timer. It's cortex m7 (stm32h7a3zi)

[MM..1]

Try without trigger, set conversion time and continuos mode. If work porblem is timer...

[Emilmart · Accepted solution]

I'm sure that it may work like you said, but in the mean time I use the following workaround which fix the problem:

- keep DCache enabled in cubeMX

- disable DCache in main usercode (SCB_DisableDCache();)

thanks

[AntoR]

I've same problem and what you suggest work, but, why appear this problem?

Thanks

A.R.