DMA + ADC doesn't work

[Stecklo]

CubeIDE 1.1.0

STM32Cube_FW_WB_V1.3.0

Trying to make DMA transfer ADC results.

I'm putting code in main() after MX_..._Init() and before while(1) {}

HAL_ADC_Start_IT(&hadc1); works fine

HAL_DMA_Start_IT(&hdma_memtomem_dma1_channel2, (uint32_t) src, (uint32_t) dest, 40); works fine too

but

HAL_ADC_Start_DMA(&hadc1, dest, 10) doesn't work as it should

ADC is activated and keeps throwing Overrun_Error

But DMA doesn't transfer anything

static void MX_ADC1_Init(void)
{
 
  /* USER CODE BEGIN ADC1_Init 0 */
 
  /* USER CODE END ADC1_Init 0 */
 
  ADC_ChannelConfTypeDef sConfig = {0};
 
  /* USER CODE BEGIN ADC1_Init 1 */
 
  /* USER CODE END ADC1_Init 1 */
  /** Common config 
  */
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV8;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.ScanConvMode = ADC_SCAN_DISABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  hadc1.Init.LowPowerAutoWait = DISABLE;
  hadc1.Init.ContinuousConvMode = ENABLE;
  hadc1.Init.NbrOfConversion = 1;
  hadc1.Init.DiscontinuousConvMode = DISABLE;
  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc1.Init.DMAContinuousRequests = ENABLE;
  hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
  hadc1.Init.OversamplingMode = ENABLE;
  hadc1.Init.Oversampling.Ratio = ADC_OVERSAMPLING_RATIO_16;
  hadc1.Init.Oversampling.RightBitShift = ADC_RIGHTBITSHIFT_NONE;
  hadc1.Init.Oversampling.TriggeredMode = ADC_TRIGGEREDMODE_SINGLE_TRIGGER;
  hadc1.Init.Oversampling.OversamplingStopReset = ADC_REGOVERSAMPLING_CONTINUED_MODE;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Regular Channel 
  */
  sConfig.Channel = ADC_CHANNEL_5;
  sConfig.Rank = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLETIME_2CYCLES_5;
  sConfig.SingleDiff = ADC_DIFFERENTIAL_ENDED;
  sConfig.OffsetNumber = ADC_OFFSET_NONE;
  sConfig.Offset = 0;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN ADC1_Init 2 */
 
  /* USER CODE END ADC1_Init 2 */
 
}

static void MX_DMA_Init(void) 
{
 
  /* DMA controller clock enable */
  __HAL_RCC_DMAMUX1_CLK_ENABLE();
  __HAL_RCC_DMA1_CLK_ENABLE();
 
  /* Configure DMA request hdma_memtomem_dma1_channel2 on DMA1_Channel2 */
  hdma_memtomem_dma1_channel2.Instance = DMA1_Channel2;
  hdma_memtomem_dma1_channel2.Init.Request = DMA_REQUEST_MEM2MEM;
  hdma_memtomem_dma1_channel2.Init.Direction = DMA_MEMORY_TO_MEMORY;
  hdma_memtomem_dma1_channel2.Init.PeriphInc = DMA_PINC_ENABLE;
  hdma_memtomem_dma1_channel2.Init.MemInc = DMA_MINC_ENABLE;
  hdma_memtomem_dma1_channel2.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
  hdma_memtomem_dma1_channel2.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
  hdma_memtomem_dma1_channel2.Init.Mode = DMA_NORMAL;
  hdma_memtomem_dma1_channel2.Init.Priority = DMA_PRIORITY_LOW;
  if (HAL_DMA_Init(&hdma_memtomem_dma1_channel2) != HAL_OK)
  {
    Error_Handler( );
  }
 
  /* DMA interrupt init */
  /* DMA1_Channel1_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 15, 0);
  HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);
 
}

void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(hadc->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspInit 0 */
 
  /* USER CODE END ADC1_MspInit 0 */
    /* Peripheral clock enable */
    __HAL_RCC_ADC_CLK_ENABLE();
  
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**ADC1 GPIO Configuration    
    PA0     ------> ADC1_IN5
    PA1     ------> ADC1_IN6 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
    /* ADC1 DMA Init */
    /* ADC1 Init */
    hdma_adc1.Instance = DMA1_Channel1;
    hdma_adc1.Init.Request = DMA_REQUEST_ADC1;
    hdma_adc1.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_adc1.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_adc1.Init.MemInc = DMA_MINC_ENABLE;
    hdma_adc1.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_adc1.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_adc1.Init.Mode = DMA_NORMAL;
    hdma_adc1.Init.Priority = DMA_PRIORITY_HIGH;
    if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)
    {
      Error_Handler();
    }
 
    __HAL_LINKDMA(hadc,DMA_Handle,hdma_adc1);
 
  /* USER CODE BEGIN ADC1_MspInit 1 */
 
  /* USER CODE END ADC1_MspInit 1 */
  }
 
}

I've tried this confuguration on PNUCLEO-WB55 Dongle in far more complex code and it worked. Now I'm using custom board and just main() body. But I think the board should not matter as DMA is totally internal thing

[Ozone]

I don't know the WB55 device, and usually do not play with Cube code.

Have you checked the DMA (instance/channel) is correct ?

[Stecklo]

I'm away from my PC now. But the code above looks like it should work (it is all auto generated by CubeMX). Altough I can't see the explicit initialization of hadc->DMA_handle. But Ithink it is handled in __HAL_LINKDMA()

[waclawek.jan]

Read out and check the DMA and DMAMUX registers.

> hdma_memtomem_dma1_channel2.Init.Request = DMA_REQUEST_MEM2MEM;

> hdma_memtomem_dma1_channel2.Init.Direction = DMA_MEMORY_TO_MEMORY;

Most probably not.

JW

[Stecklo]

@Community member​ , you were right.

DMAMUX_CxCR is empty

This line does nothing. While operands are 5 and 255. The result should be 5, but CCR is 0.

HAL_StatusTypeDef HAL_DMA_Init(DMA_HandleTypeDef *hdma) 
{
    <...>
    hdma->DMAmuxChannel->CCR = (hdma->Init.Request & DMAMUX_CxCR_DMAREQ_ID);
    <...>
}

I havent located the reason so far, but this is a good clue.

[Stecklo · Accepted solution]

The answer is to put

MX_DMA_Init();

before

MX_ADC1_Init();

As the first one calls

__HAL_RCC_DMAMUX1_CLK_ENABLE();

 __HAL_RCC_DMA1_CLK_ENABLE();

[Stecklo]

Is there any way to make CubeMX aka Device Configuration Tool to change the Init functions order? There is a corresponding view in Project Manager tab, but the order seems to be fixed.

[Stecklo]

Well, I've changed the order manually editing .ioc file with text editor. But the whole thing should be considered as a CubeMX bug

[Amel NASRI]

Hello,

Glad that you found the root cause of your issue.

I'll report this limitation to our STM32CubeMX team.

-Amel

[Nesrine.JLASSI]

Hello @Community member​ 

Thanks for the feedback,

It will be fixed on the next version of CubeMX.

Best regards,

Nesrine