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Problem in using DMA for ADC Fast Interleaved mode in STM32F103VET

Question asked by keshavarz.abbas on Apr 28, 2013
Latest reply on Apr 30, 2013 by keshavarz.abbas

I configured ADC1 and ADC2 on fast interleaved mode and use DMA for ADC data transfer. I expect that when I call the StartConversion function of ADC1, the ADC2 should be started automatically by ADC1 after 7 ADC clock cycle and inversely ADC2 restart ADC1 continuously .  but when I start ADC1, ADC2 does not work. for bypassing this problem, I manually started both ADCs. in this situation, both ADCs work but the DMA output is not continuous i.e. in regular time intervals, it seems that the ADCs values is not transferred by DMA. I found it because I had known the input signal in my experiment.

I couldn’t find any example for this use in STM32F10x in ST site or STD_PERIPH examples or internet. I urgently need to know what the problem is.

Please help me if you have passed this issue or know what the wrong is


my code in main() is

ADC_SoftwareStartConvCmd(ADC1, ENABLE); // start the process


DMA_ClearFlag ( DMA1_FLAG_TC1 ) ;

the config of ADC is as below

 ADC_InitStructure.ADC_Mode = ADC_Mode_FastInterl;
 ADC_InitStructure.ADC_ScanConvMode = DISABLE;
 ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
 ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
 ADC_InitStructure.ADC_NbrOfChannel = 1;
 RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);   
 ADC_DeInit(ADC1);    ADC_Init(ADC1, &ADC_InitStructure);
 ADC_RegularChannelConfig(ADC1, ADC_Channel_15, 1, ADC_SampleTime_1Cycles5);  

RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC2, ENABLE);   
ADC_Init(ADC2, &ADC_InitStructure);
ADC_RegularChannelConfig(ADC2, ADC_Channel_15, 1, ADC_SampleTime_1Cycles5);  ADC_Cmd(ADC1, ENABLE);

and the config of DMA is

  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); /* Enable DMA clock */

  DMA_Cmd(DMA1_Channel1, DISABLE);             


  DMA_InitStructure->DMA_PeripheralBaseAddr = (uint32_t) ADC1_DR_Address;

  DMA_InitStructure->DMA_MemoryBaseAddr = (uint32_t) data_buffer;

  DMA_InitStructure->DMA_DIR = DMA_DIR_PeripheralSRC;

  DMA_InitStructure->DMA_BufferSize = BuffSIZE;

  DMA_InitStructure->DMA_PeripheralInc = DMA_PeripheralInc_Disable;

  DMA_InitStructure->DMA_MemoryInc = DMA_MemoryInc_Enable;

  DMA_InitStructure->DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;

  DMA_InitStructure->DMA_MemoryDataSize = DMA_MemoryDataSize_Word;

  DMA_InitStructure->DMA_Mode = DMA_Mode_Circular;

  DMA_InitStructure->DMA_Priority = DMA_Priority_VeryHigh;

  DMA_InitStructure->DMA_M2M = DMA_M2M_Disable;

  DMA_Init(DMA1_Channel1, DMA_InitStructure);

  DMA_Cmd(DMA1_Channel1, ENABLE);