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stm32-rs / stm32f4xx-hal

A Rust embedded-hal HAL for all MCUs in the STM32 F4 family
BSD Zero Clause License
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Implement DMA for DualI2s. #752

Open ProjectRobal opened 6 months ago

ProjectRobal commented 6 months ago

Hello, I want to read audio data from ADC using I2S of STM32F411 microcontroller. I want to use DMA to do so. But I have no idea how to configure it. I have created a topic on the rust embedded forum, searching for a solution: https://users.rust-lang.org/t/dma-configuration-for-duali2s/110411 And one of the answers suggests that I cannot use DMA with DualI2s because of HAL oversight. Is that true or am I missing something?

burrbull commented 6 months ago

I don't know who can help you with this. Maybe @YruamaLairba ?

YruamaLairba commented 6 months ago

And one of the answers suggests that I cannot use DMA with DualI2s because of HAL oversight. Is that true or am I missing something?

it's unfortunately true, it's currently impossible to use DMA with "DualI2s" without bypassing the HAL and doing dirty things. You can't create a "Transfer" around a "DualI2s" because "Transfer" system is build with the idea that one driver hold one peripheral, which is not the case with "DualI2s".

And, In my opinion, in many situation, "Transfer" system is not appropriate. For example it's impossible to share a device across interruption because Transfer need ownership of the device