AnsweredAssumed Answered

ADC DMA wonder

Question asked by bit.udi on Jun 23, 2011
Latest reply on Sep 18, 2013 by fm
Hi,
I convert two adc channels(1,2) and using DMA to transfer them to memory.
ADC channel1 -> MemConvertedValue[0]
ADC channel2 -> MemConvertedValue[1]
Normaly it works OK, but while i am in debug mode and ocusenly pressing the reset icon in IAR, i have noticed that the DMA has swaped memory locatins:
ADC channel1 -> MemConvertedValue[1]
ADC channel2 -> MemConvertedValue[0]
Can any one know why?

Here is the configuration code i did:
  
  /* DMA1 channel1 configuration ----------------------------------------------*/
  DMA_DeInit(DMA1_Channel1);
  
  DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;
  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&MemConvertedValue;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
  DMA_InitStructure.DMA_BufferSize = 2;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  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_M2M = DMA_M2M_Disable;
 
  DMA_Init(DMA1_Channel1, &DMA_InitStructure);
  
  DMA_Cmd(DMA1_Channel1, ENABLE);
  
  /* Enable ADC1 DMA */
  ADC_DMACmd(ADC1, ENABLE);

  ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
  ADC_InitStructure.ADC_ScanConvMode = ENABLE;
  ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; 
  ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
  ADC_InitStructure.ADC_NbrOfChannel = 2;
 
  ADC_Init(ADC1, &ADC_InitStructure);
  ADC_RegularChannelConfig(ADC1, MW_Channel_1, 1, ADC_SampleTime_55Cycles5);
  ADC_RegularChannelConfig(ADC1, MW_Channel_2, 2, ADC_SampleTime_55Cycles5);

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

  /* Enable ADC1 reset calibaration register */
  ADC_ResetCalibration(ADC1);
  /* Check the end of ADC1 reset calibration register */
  while(ADC_GetResetCalibrationStatus(ADC1));
  /* Start ADC1 calibaration */
  ADC_StartCalibration(ADC1);
  /* Check the end of ADC1 calibration */
  while(ADC_GetCalibrationStatus(ADC1));


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