I am trying to read ADC values on the Nucleo-F722ZE board.
- I have 3V from a power supply connected to pin PA3 on the Nucleo. Verified that the pin on the processor reads 3V.
- Grounds from the power supply and the Nucleo are connected.
- I checked the voltages on AVDD/VREF, they are correct at ~3.3V
However, when I read the ADC value, it shows up as ~600. 3V should give me ~3700. I have tried varying power supply voltage so that the voltage at the pin is 1V to 3V, however the values from the ADC remain constant at ~630.
I have tried the other two pins initialized in my code, PC0 and PC3, and they behave the same way.
I have a suspicion that the ADC is not configured properly. Is there something wrong with my code?
ADC_HandleTypeDef hadc1;
DMA_HandleTypeDef hdma_adc1;
/* ADC1 init function */
void MX_ADC1_Init(void)
{
ADC_ChannelConfTypeDef sConfig;
hadc1.Instance = ADC1;
hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.ScanConvMode = ENABLE;
hadc1.Init.ContinuousConvMode = ENABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.NbrOfConversion = 5;
hadc1.Init.DMAContinuousRequests = ENABLE;
hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_56CYCLES;
sConfig.Offset = 0;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_1;
sConfig.Rank = 2;
sConfig.SamplingTime = ADC_SAMPLETIME_56CYCLES;
sConfig.Offset = 0;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_2;
sConfig.Rank = 3;
sConfig.SamplingTime = ADC_SAMPLETIME_56CYCLES;
sConfig.Offset = 0;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_VREFINT;
sConfig.Rank = 4;
sConfig.SamplingTime = ADC_SAMPLETIME_56CYCLES;
sConfig.Offset = 0;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
sConfig.Rank = 5;
sConfig.SamplingTime = ADC_SAMPLETIME_56CYCLES;
sConfig.Offset = 0;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
}
void HAL_ADC_MspInit(ADC_HandleTypeDef* adcHandle)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(adcHandle->Instance==ADC1)
{
/* USER CODE BEGIN ADC1_MspInit 0 */
/* USER CODE END ADC1_MspInit 0 */
/* ADC1 clock enable */
__HAL_RCC_ADC1_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_0||GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
/* ADC1 DMA Init */
/* ADC1 Init */
hdma_adc1.Instance = DMA2_Stream0;
hdma_adc1.Init.Channel = DMA_CHANNEL_0;
hdma_adc1.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_adc1.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_adc1.Init.MemInc = DMA_MINC_ENABLE;
hdma_adc1.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
hdma_adc1.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
hdma_adc1.Init.Mode = DMA_CIRCULAR;
hdma_adc1.Init.Priority = DMA_PRIORITY_LOW;
hdma_adc1.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
__HAL_LINKDMA(adcHandle,DMA_Handle,hdma_adc1);
/* ADC1 interrupt Init */
HAL_NVIC_SetPriority(ADC_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(ADC_IRQn);
/* USER CODE BEGIN ADC1_MspInit 1 */
/* USER CODE END ADC1_MspInit 1 */
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
/**Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = 16;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_USART3;
PeriphClkInitStruct.Usart3ClockSelection = RCC_USART3CLKSOURCE_PCLK1;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure the Systick interrupt time
*/
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
/**Configure the Systick
*/
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
/* SysTick_IRQn interrupt configuration */
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}
int main(void)
{
uint32_t ADC_Raw[5] = {0};
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_DMA_Init();
MX_ADC1_Init();
MX_TIM1_Init();
MX_USART3_UART_Init();
MX_TIM3_Init();
MX_NVIC_Init();
sprintf(buffer, "Nucleo Phase Shift\n");
print((char *)buffer);
HAL_ADC_Start_DMA(&hadc1, (uint32_t *)&ADC_Raw, sizeof(ADC_Raw));
HAL_Delay(250);
while (1)
{
}
}