In the case of STM32U575ZIQ, Can I use an external DMA (and not the internal I-DMA) to interface the SDMMC card?

[ANalg.1]

Basically, when I use the IDMA of STM32U5, there is a significant delay happening while communicating with the card. And if I do the same by using STM32F4(which uses general DMA), then there is not such a huge delay. After checking other parameters (transfer block size, I-cache, D-cache, etc) I suspect that, if I use the external DMA then, will the delay issue gets solved.

In the ref manual, I do not see the GPDMA request along with SDMMC.

So, please inform me if I can use GPDMA to configure the SDMMC and suggest your views on the mentioned issue.

[Mohamed Aymen HZAMI]

Hello @ANalg.1​ and welcome to the community,

You can refer to this Fimeware example : "STM32Cube\Repository\STM32Cube_FW_U5_V1.1.1\Projects\STM32U575I-EV\Examples\SD\SD_ReadWrite_DMALinkedList"

And also there is the how to use the GPDMA for STM32U5 application note

Aymen