ADC not working on STM32H753. It keeps reading 0.

[Askia]

I used this sample code I took somewhere to try out but the ADC is not working on STM32H753.

It keeps reading 0. Can anyone help?

#include "main.h"
#include <stdio.h>
#include <stdint.h>
#include "uart.h"
/* Definition for ADCx clock resources */
#define ADCx                            ADC1
#define ADCx_CLK_ENABLE()               __HAL_RCC_ADC12_CLK_ENABLE()
#define ADCx_CHANNEL_GPIO_CLK_ENABLE()  __HAL_RCC_GPIOA_CLK_ENABLE()

#define ADCx_FORCE_RESET()              __HAL_RCC_ADC12_FORCE_RESET()
#define ADCx_RELEASE_RESET()            __HAL_RCC_ADC12_RELEASE_RESET()

/* Definition for ADCx Channel Pin */
#define ADCx_CHANNEL_PIN                GPIO_PIN_0
#define ADCx_CHANNEL_GPIO_PORT          GPIOA

/* Definition for ADCx's Channel */
#define ADCx_CHANNEL                    ADC_CHANNEL_0
#define SAMPLINGTIME                    ADC_SAMPLETIME_8CYCLES_5

/* ADC handler declaration */
ADC_HandleTypeDef    AdcHandle;

/* Variable used to get converted value */
__IO uint16_t uhADCxConvertedValue = 0;

void SystemClock_Config(void);
static void MPU_Config(void);
static void MX_GPIO_Init(void);

int main(void)
{
 ADC_ChannelConfTypeDef sConfig;

  MPU_Config();
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  UART_Init();
 
  /*##-1- Configure the ADC peripheral #######################################*/
  AdcHandle.Instance          = ADCx;
 
  HAL_ADC_DeInit(&AdcHandle);
  AdcHandle.Init.ClockPrescaler           = ADC_CLOCK_ASYNC_DIV2;          /* Asynchronous clock mode, input ADC clock divided by 2*/
  AdcHandle.Init.Resolution               = ADC_RESOLUTION_16B;            /* 16-bit resolution for converted data */
  AdcHandle.Init.ScanConvMode             = DISABLE;                       /* Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1) */
  AdcHandle.Init.EOCSelection             = ADC_EOC_SINGLE_CONV;           /* EOC flag picked-up to indicate conversion end */
  AdcHandle.Init.LowPowerAutoWait         = DISABLE;                       /* Auto-delayed conversion feature disabled */
  AdcHandle.Init.ContinuousConvMode       = DISABLE;                       /* Continuous mode disabled to have only 1 conversion at each conversion trig */
  AdcHandle.Init.NbrOfConversion          = 1;                             /* Parameter discarded because sequencer is disabled */
  AdcHandle.Init.DiscontinuousConvMode    = DISABLE;                       /* Parameter discarded because sequencer is disabled */
  AdcHandle.Init.NbrOfDiscConversion      = 1;                             /* Parameter discarded because sequencer is disabled */
  AdcHandle.Init.ExternalTrigConv         = ADC_SOFTWARE_START;            /* Software start to trig the 1st conversion manually, without external event */
  AdcHandle.Init.ExternalTrigConvEdge     = ADC_EXTERNALTRIGCONVEDGE_NONE; /* Parameter discarded because software trigger chosen */
  AdcHandle.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DR;         /* Regular Conversion data stored in DR register only */
  AdcHandle.Init.Overrun                  = ADC_OVR_DATA_OVERWRITTEN;      /* DR register is overwritten with the last conversion result in case of overrun */
  AdcHandle.Init.OversamplingMode         = DISABLE;                       /* No oversampling */

  HAL_ADC_Init(&AdcHandle);

  /*##-2- Configure ADC regular channel ######################################*/
  sConfig.Channel      = ADCx_CHANNEL;                /* Sampled channel number */
  sConfig.Rank         = ADC_REGULAR_RANK_1;          /* Rank of sampled channel number ADCx_CHANNEL */
  sConfig.SamplingTime = ADC_SAMPLETIME_387CYCLES_5;    /* Sampling time (number of clock cycles unit) */
  sConfig.SingleDiff   = ADC_SINGLE_ENDED;            /* Single-ended input channel */
  sConfig.OffsetNumber = ADC_OFFSET_NONE;             /* No offset subtraction */
  sConfig.Offset = 0;                                 /* Parameter discarded because offset correction is disabled */

  HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
 
  /* Run the ADC calibration in single-ended mode */
  HAL_ADCEx_Calibration_Start(&AdcHandle, ADC_CALIB_OFFSET_LINEARITY, ADC_SINGLE_ENDED);
 

  while (1)
  {
  /*##-3- Start the conversion process #######################################*/
  HAL_ADC_Start(&AdcHandle);
 
  HAL_ADC_PollForConversion(&AdcHandle, 1000);
 
    /* ADC conversion completed */
    /*##-5- Get the converted value of regular channel  ########################*/
  uhADCxConvertedValue = HAL_ADC_GetValue(&AdcHandle);
    printf("Starting ....  %d \r\n", uhADCxConvertedValue);
  }
}

// GPIO Initialization for PA0 as Analog
static void MX_GPIO_Init(void)
{
   __HAL_RCC_GPIOA_CLK_ENABLE();  // Enable clock for GPIOA
   GPIO_InitTypeDef GPIO_InitStruct = {0};
   GPIO_InitStruct.Pin = GPIO_PIN_0;           // Select PA0
   GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;    // Set as analog mode
   GPIO_InitStruct.Pull = GPIO_NOPULL;         // No pull-up or pull-down
   HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);     // Initialize PA0
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_DIV1;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 4;
  RCC_OscInitStruct.PLL.PLLN = 50;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
                              |RCC_CLOCKTYPE_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}


void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};

  /* Disables the MPU */
  HAL_MPU_Disable();

  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.BaseAddress = 0x0;
  MPU_InitStruct.Size = MPU_REGION_SIZE_4GB;
  MPU_InitStruct.SubRegionDisable = 0x87;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_NO_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
}

void Error_Handler(void)
{
   __disable_irq();
  while (1)
  {
  }
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @PAram file: pointer to the source file name
  * @PAram line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

[Chris21]

You have: #define ADCx_CLK_ENABLE() __HAL_RCC_ADC12_CLK_ENABLE()

but do you ever actually use it?

[Askia]

Not really. In fact, I tried multiple times and couldn't get it to work, so I resolved to trying out an already working code on PA0 for testing and guidance. 

[Chris21]

The ADC will definitely not work if its clock has not been enabled.

[Askia]

I enabled it and tested it but it's still not working. Only reading 0

[Andrew Neil]

Please see the Posting Tips for how to properly post source code:

https://community.st.com/t5/community-guidelines/how-to-write-your-question-to-maximize-your-chances-to-find-a/ta-p/575228

I edited the post for you

[Karl Yamashita]

You don't check HAL status so how do you know if it returned HAL_OK, HAL_ERROR, or HAL_TIMEOUT?

HAL_ADC_PollForConversion(&AdcHandle, 1000);

A better approach would be

	if(HAL_ADC_PollForConversion(&AdcHandle, 100) == HAL_OK)
	{
		/* ADC conversion completed */
		/*##-5- Get the converted value of regular channel  ########################*/
		uhADCxConvertedValue = HAL_ADC_GetValue(&AdcHandle);
		printf("Starting ....  %d \r\n", uhADCxConvertedValue);
	}
	else 
	{
		// handle error or timeout
	}