AnsweredAssumed Answered

ADC + DMA (8Channels) Aleatory Crash

Question asked by amaral.guilherme on Mar 17, 2015
Latest reply on Mar 17, 2015 by Clive One
Hello,

I've an application that need the reading of 8 ADC channels...
I had thought use DMA in order to collect a big amount of data and then calc the average.

Everything works great! However, sometimes, in an aleatory way, the code crashes! :-(

Any suspicion?

Here is my configuration:


#define NSAMPLES    35
#define NUM_CHANNELS    8
#define DMA_BUFFER_SIZE (NSAMPLES*NUM_CHANNELS)

void ADC_Configuration(void)
{
  ADC_InitTypeDef       ADC_InitStructure;
  ADC_CommonInitTypeDef ADC_CommonInitStructure;
  DMA_InitTypeDef       DMA_InitStructure;
 
  /* Enable peripheral clocks *************************************************/
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE); NO init params
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
 
  /* DMA2_Stream0 channel0 configuration **************************************/
  DMA_DeInit(DMA2_Stream0);
  DMA_InitStructure.DMA_Channel = DMA_Channel_0;
  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(ADC1->DR);
  DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)ADC1_Buff;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
  DMA_InitStructure.DMA_BufferSize = DMA_BUFFER_SIZE;
  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_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);
  /* DMA2_Stream0 enable */
  DMA_Cmd(DMA2_Stream0, ENABLE);
  
  /* Configure ADC1 Channels pins as analog input ******************************/
  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_2  |  GPIO_Pin_3 |  GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6 ;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  
  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_4;
  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_Cmd(ADC1, DISABLE);
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ScanConvMode = ENABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfConversion = NUM_CHANNELS;
ADC_InitStructure.ADC_ExternalTrigConv = 0x00;
ADC_Init(ADC1, &ADC_InitStructure);
  
/* Enable ADC1 DMA */
ADC_DMACmd(ADC1, ENABLE);

ADC_RegularChannelConfig(ADC1, ADC_Channel_3 , 1, ADC_SampleTime_480Cycles);  
ADC_RegularChannelConfig(ADC1, ADC_Channel_11, 2, ADC_SampleTime_480Cycles);  
ADC_RegularChannelConfig(ADC1, ADC_Channel_2 , 3, ADC_SampleTime_480Cycles); 
ADC_RegularChannelConfig(ADC1, ADC_Channel_6 , 4, ADC_SampleTime_480Cycles); 
ADC_RegularChannelConfig(ADC1, ADC_Channel_5 , 5, ADC_SampleTime_480Cycles); 
ADC_RegularChannelConfig(ADC1, ADC_Channel_4 , 6, ADC_SampleTime_480Cycles);  
ADC_RegularChannelConfig(ADC1, ADC_Channel_10, 7, ADC_SampleTime_480Cycles); 
ADC_RegularChannelConfig(ADC1, ADC_Channel_14, 8, ADC_SampleTime_480Cycles);  
    
  /* Enable DMA request after last transfer (Single-ADC mode) */
  ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
  
  ADC_ContinuousModeCmd(ADC1, ENABLE);

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

    Delay_ms(100);
    /* Start ADC1 Software Conversion */
    ADC_SoftwareStartConv(ADC1);
}



Thanks in advance!

Best regards,
--
Guilherme

Outcomes