I am trying to use ADC with 2 channels and DMA, but I only get 1 reading before the overrun bit gets set. Also the 1 reading is wrong, I am expecting a value of approx 2100, but I am getting around 70. I can see in the hadc->DR that the value are correct, but it is not transferred to the array somehow (adc_value in runADC200Hz function below).
here is the code I am using:
main.c:
static void MX_ADC_Init(void)
{
ADC_ChannelConfTypeDef sConfig = {0};
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc.Instance = ADC1;
hadc.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
hadc.Init.Resolution = ADC_RESOLUTION_12B;
hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD;
hadc.Init.EOCSelection = ADC_EOC_SEQ_CONV;
hadc.Init.LowPowerAutoWait = DISABLE;
hadc.Init.LowPowerAutoPowerOff = DISABLE;
hadc.Init.ContinuousConvMode = ENABLE;
hadc.Init.DiscontinuousConvMode = DISABLE;
hadc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc.Init.DMAContinuousRequests = ENABLE;
hadc.Init.Overrun = ADC_OVR_DATA_PRESERVED;
if (HAL_ADC_Init(&hadc) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
sConfig.SamplingTime = ADC_SAMPLETIME_71CYCLES_5;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_1;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
Error_Handler();
}
}
static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();
/* DMA interrupt init */
/* DMA1_Channel1_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 3, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);
}
stm32f0xx_hal_msp.c:
void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(hadc->Instance==ADC1)
{
/* Peripheral clock enable */
__HAL_RCC_ADC1_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
/**ADC GPIO Configuration
PA0 ------> ADC_IN0
PA1 ------> ADC_IN1
*/
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 */
/* ADC Init */
hdma_adc.Instance = DMA1_Channel1;
hdma_adc.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_adc.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_adc.Init.MemInc = DMA_MINC_ENABLE;
hdma_adc.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
hdma_adc.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
hdma_adc.Init.Mode = DMA_CIRCULAR;
hdma_adc.Init.Priority = DMA_PRIORITY_LOW;
if (HAL_DMA_Init(&hdma_adc) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(hadc,DMA_Handle,hdma_adc);
/* ADC1 interrupt Init */
HAL_NVIC_SetPriority(ADC1_COMP_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(ADC1_COMP_IRQn);
}
}
stm32f0xx_it.c
void DMA1_Channel1_IRQHandler(void)
{
HAL_DMA_IRQHandler(&hdma_adc);
}
/**
* @brief This function handles ADC and COMP interrupts (COMP interrupts through EXTI lines 21 and 22).
*/
void ADC1_COMP_IRQHandler(void)
{
HAL_ADC_IRQHandler(&hadc);
}
I am running the ADC every 5ms like this:
static uint32_t adc_value[2];
void runADC200Hz(void)
{
if (HAL_ADC_Start_DMA(&hadc, (uint32_t*) &adc_value[0], 2) != HAL_OK){
asm("nop");
}
}
After the first conversion these flags are set:
- ADC ready (ADRDY)
- End of sampling (EOSMP)
- End of conversion (EOC)
- End of sequence (EOS)
- ADC overrun (OVR)
I have been setting up ADC with DMA several times before with no problems, but that was on F2 and F7. Strange thing is that I have access to another code which works for the exact same chip, with the exact same code I have written above. I have no idea where I should look and compare beyond those functions above. Any suggestion on what Im doing wrong here? I have tried every type of sampletime but it is the same result. thanks for any comments!
