STM32f4 ADC1 Dma configuration not working

Question

I am trying to configure ADC1 and run it. Using STM Peripheral examples for ADC3 with DMA. In example I can see the changes in ADC3ConvertedValue. Here is example of working code:

    #include "stm32f4_discovery.h"
    #include <stdio.h>

    #define ADC3_DR_ADDRESS     ((uint32_t)0x4001224C)

    __IO uint16_t ADC3ConvertedValue = 0;
    __IO uint32_t ADC3ConvertedVoltage = 0;

    void ADC3_CH12_DMA_Config(void);


    int main(void)
    {

      ADC3_CH12_DMA_Config();

      ADC_SoftwareStartConv(ADC3);

      while (1)
      {
      /* convert the ADC value (from 0 to 0xFFF) to a voltage value (from 0V to       3.3V)*/
        ADC3ConvertedVoltage = ADC3ConvertedValue *3300/0xFFF;
  }
}


    void ADC3_CH12_DMA_Config(void)
    {
       ADC_InitTypeDef       ADC_InitStructure;
      ADC_CommonInitTypeDef ADC_CommonInitStructure;
      DMA_InitTypeDef       DMA_InitStructure;
      GPIO_InitTypeDef      GPIO_InitStructure;


      RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2 | RCC_AHB1Periph_GPIOC,  ENABLE);
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC3, ENABLE);

      /* DMA2 Stream0 channel0 configuration **************************************/
      DMA_InitStructure.DMA_Channel = DMA_Channel_2;  
      DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC3_DR_ADDRESS;
      DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&ADC3ConvertedValue;
      DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
      DMA_InitStructure.DMA_BufferSize = 1;
      DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
      DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
      DMA_InitStructure.DMA_PeripheralDataSize =      DMA_PeripheralDataSize_HalfWord;
      DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
      DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
      DMA_InitStructure.DMA_Priority = DMA_Priority_High;
      DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         
      DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
      DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
      DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
      DMA_Init(DMA2_Stream0, &DMA_InitStructure);
      DMA_Cmd(DMA2_Stream0, ENABLE);

  /* Configure ADC3 Channel12 pin as analog input ******************************/
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
      GPIO_Init(GPIOC, &GPIO_InitStructure);

      /* ADC Common Init **********************************************************/
      ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
      ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
      ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
      ADC_CommonInitStructure.ADC_TwoSamplingDelay =    ADC_TwoSamplingDelay_5Cycles;
      ADC_CommonInit(&ADC_CommonInitStructure);

      /* ADC3 Init ****************************************************************/
      ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
      ADC_InitStructure.ADC_ScanConvMode = DISABLE;
      ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
      ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
      ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
      ADC_InitStructure.ADC_NbrOfConversion = 1;
      ADC_Init(ADC3, &ADC_InitStructure);

       /* ADC3 regular channel12 configuration *************************************/
      ADC_RegularChannelConfig(ADC3, ADC_Channel_12, 1, ADC_SampleTime_3Cycles);

     /* Enable DMA request after last transfer (Single-ADC mode) */
      ADC_DMARequestAfterLastTransferCmd(ADC3, ENABLE);

      /* Enable ADC3 DMA */
      ADC_DMACmd(ADC3, ENABLE);

      /* Enable ADC3 */
      ADC_Cmd(ADC3, ENABLE);
     }

Here is my code with ADC1 configuration:

    /**
  ******************************************************************************
  * @file    ADC1_DMA/main.c 

    /* Includes ------------------------------------------------------------------*/
    #include "stm32f4_discovery.h"
    #include <stdio.h>

    #define ADC1_DR_ADDRESS     ((uint32_t)0x4001204C)

    __IO uint16_t ADC1ConvertedValue = 0;
    __IO uint32_t ADC1ConvertedVoltage = 0;

    void ADC1_CH12_DMA_Config(void);


    int main(void)
    {

      ADC1_CH12_DMA_Config();

      ADC_SoftwareStartConv(ADC1);

      while (1)
      {
      /* convert the ADC value (from 0 to 0xFFF) to a voltage value (from 0V to 3.3V)*/
        ADC1ConvertedVoltage = ADC1ConvertedValue *3300/0xFFF;
      }
    }

    void ADC1_CH12_DMA_Config(void)
    {
      ADC_InitTypeDef       ADC_InitStructure;
      ADC_CommonInitTypeDef ADC_CommonInitStructure;
      DMA_InitTypeDef       DMA_InitStructure;
      GPIO_InitTypeDef      GPIO_InitStructure;

      /* Enable ADC1, DMA2 and GPIO clocks ****************************************/
      RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2 | RCC_AHB1Periph_GPIOC, ENABLE);
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

      /* DMA2 Stream0 channel0 configuration **************************************/
      DMA_InitStructure.DMA_Channel = DMA_Channel_2;  
      DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_ADDRESS;
      DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&ADC1ConvertedValue;
      DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
      DMA_InitStructure.DMA_BufferSize = 1;
      DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
      DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
      DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
      DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
      DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
      DMA_InitStructure.DMA_Priority = DMA_Priority_High;
      DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         
      DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
      DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
      DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
      DMA_Init(DMA2_Stream0, &DMA_InitStructure);
      DMA_Cmd(DMA2_Stream0, ENABLE);

      /* Configure ADC1 Channel12 pin as analog input ******************************/
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
      GPIO_Init(GPIOC, &GPIO_InitStructure);

      /* ADC Common Init **********************************************************/
      ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
      ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
      ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
      ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
      ADC_CommonInit(&ADC_CommonInitStructure);

      /* ADC1 Init ****************************************************************/
      ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
      ADC_InitStructure.ADC_ScanConvMode = DISABLE;
      ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
      ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
      ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
      ADC_InitStructure.ADC_NbrOfConversion = 1;
      ADC_Init(ADC1, &ADC_InitStructure);

     /* ADC1 regular channel12 configuration *************************************/
      ADC_RegularChannelConfig(ADC1, ADC_Channel_12, 1, ADC_SampleTime_3Cycles);


     /* Enable DMA request after last transfer (Single-ADC mode) */
      ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);

      /* Enable ADC1 DMA */
      ADC_DMACmd(ADC1, ENABLE);

      /* Enable ADC1 */
      ADC_Cmd(ADC1, ENABLE);
     }

In ADC1ConvertedValue I always see zeroes. I replaced

DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_ADDRESS;

with

DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) & (ADC1->DR);

and still see zeroes.

Clifford Clifford · Accepted Answer · 2016-12-08T20:51:42

You need to reference the DMA2 request mapping table in the reference manual applicable to the STM32F4xx part you are using:

As you can see ADC1 is on Channel 0/Streams 0 & 4, while ADC3 is on Channel 2/Streams 0 & 1.

So the change is:

 /* DMA2 Stream0 channel0 configuration **************************************/
  DMA_InitStructure.DMA_Channel = DMA_Channel_0;

Somewhat strangely, the comment was already correct, but incorrect in the ADC3 example.

STM32f4 ADC1 Dma configuration not working

1 Answers