[STM32H730ZBT] I2S no data with DMA and D-Cache enabled

sebxx4 · ‎2026-02-19

Hello,

I need to have D-Cache enabled to improve performance of FMC external SDRAM (it's >3x slower without D-Cache enabled). I also want to use I2S for audio. But with D-Cache enabled, I don't get any data from ADC. What can I do to use I2S with D-Cache enabled?

mƎALLEm · ‎2026-02-19

Hello,

You need to ensure a data coherency when it turns to the DMA usage while D-cache is enabled.

Need to perform cache maintenance by software.

Refer to the AN4839 "Level 1 cache on STM32F7 Series and STM32H7 Series", especially the section: 3.2 Example for cache maintenance and data coherency and the scenario described in it:

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View solution in original post

mƎALLEm · ‎2026-02-19

Hello,

You need to ensure a data coherency when it turns to the DMA usage while D-cache is enabled.

Need to perform cache maintenance by software.

Refer to the AN4839 "Level 1 cache on STM32F7 Series and STM32H7 Series", especially the section: 3.2 Example for cache maintenance and data coherency and the scenario described in it:

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.