ADC and DMA

[jakob.brunhart]

Hi,

I'm using ADC1 in combination with DMA (One-Shot-Mode). The ADC is used read out a spectrometer (288 pixel). Starting the read function does the following procedure:

1. HAL_ADC_Start_DMA( &hadc1, buffer, 288);
2. Wait for callback: HAL_ADC_ConvCpltCallback();
3. HAL_ADC_Stop_DMA( &hadc1 );

HAL_ADC_Stop_DMA( &hadc1 ) results in the error: HAL_DMA_ERROR_NO_XFER. The error is set in stm32h7xx_hal_dma.c (line 752).

 /* Check the DMA peripheral state */
 if(hdma->State != HAL_DMA_STATE_BUSY)
 {
 hdma->ErrorCode = HAL_DMA_ERROR_NO_XFER;
 
 /* Process Unlocked */
 __HAL_UNLOCK(hdma);
 
 return HAL_ERROR;
 }
 

The callback HAL_ADC_ConvCpltCallback(); is called by the DMA (transfer complete interrput). And here the hdma->State is set to HAL_DMA_STATE_READY.

 /* Disable the transfer complete interrupt if the DMA mode is not CIRCULAR */
 else
 {
 if((((DMA_Stream_TypeDef *)hdma->Instance)->CR & DMA_SxCR_CIRC) == RESET)
 {
 /* Disable the transfer complete interrupt */
 ((DMA_Stream_TypeDef *)hdma->Instance)->CR &= ~(DMA_IT_TC);
 
 /* Process Unlocked */
 __HAL_UNLOCK(hdma);
 
 /* Change the DMA state */
 hdma->State = HAL_DMA_STATE_READY;
 }
 
 if(hdma->XferCpltCallback != NULL)
 {
 /* Transfer complete callback */
 hdma->XferCpltCallback(hdma);
 }
 }

(line 1324 in file stm32h7xx_hal_dma.c)

In my opinion this results always in this error.

Any idea?

Regards

Jakob