How to use SDIO + DMA transfer-complete callbacks?

[omaroski]

I’m using SDIO + DMA on an STM32F407 and I need a “transfer complete” callback for SD writes/reads. 

What is the correct way to attach a user callback for SDIO + DMA completion when using the CubeMX‑generated SD/FATFS drivers?

Thank you!

[Saket_Om]

Hello ​@omaroski 

The SD driver declares the transfer-complete callbacks as weak functions, so they can be overridden by the user application.
To attach your own handling for SDIO + DMA read/write completion, simply implement these same callback functions in your application code:

void HAL_SD_TxCpltCallback(SD_HandleTypeDef *hsd)

{

}



void HAL_SD_RxCpltCallback(SD_HandleTypeDef *hsd)

{

}

 

[MOBEJ]

Hi @omaroski,

In CubeMX, configure SDIO in 1-bit mode, pull up all SDIO GPIO pins except CLK, add two DMA channels (Rx + Tx), and enable the SDIO global interrupt in the NVIC tab .

Then, redefine these weak HAL callbacks anywhere in your application:

void HAL_SD_TxCpltCallback(SD_HandleTypeDef *hsd) { }
void HAL_SD_RxCpltCallback(SD_HandleTypeDef *hsd) { }
void HAL_SD_ErrorCallback (SD_HandleTypeDef *hsd) {  }

In the Tx callback, wait for HAL_SD_GetCardState() == HAL_SD_CARD_TRANSFER before reusing the buffer, as the card may still be internally programming after the DMA transfer completes.

For a complete working reference, check the FatFs_uSD_DMA_RTOS example from the official STM32CubeH7 repository it covers exactly this pattern.

Br