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LIve Exressions says " Failed to evaluate expressions.".

MED2972
Associate III

Hi.

I am developing on STM32CubeIDE with F446RE Nucleo, and I want to get the voltage value by calculating ADC value.

But that doesn't work.

Here is the "main.c".

I made two variables.(" ADC " means ADC value, " v " means voltage value.)

Red texts are texts whose I wrote.

 
Spoiler
/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
 
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
 
/* USER CODE END PTD */
 
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
 
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
ADC_HandleTypeDef hadc1;
 
/* USER CODE BEGIN PV */
__IO uint32_t ADC;
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_ADC1_Init(void);
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
double v;
  /* USER CODE END 1 */
 
  /* MCU Configuration--------------------------------------------------------*/
 
  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();
 
  /* USER CODE BEGIN Init */
 
  /* USER CODE END Init */
 
  /* Configure the system clock */
  SystemClock_Config();
 
  /* USER CODE BEGIN SysInit */
 
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_ADC1_Init();
  /* USER CODE BEGIN 2 */
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
 
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
HAL_ADC_Start(&hadc1);
    if( HAL_ADC_PollForConversion(&hadc1, 1000) == HAL_OK ) {
 
     ADC = HAL_ADC_GetValue(&hadc1);
    v = 3.3 * ADC / 4096;
    }
    HAL_ADC_Stop(&hadc1);
  }
}
  /* USER CODE END 3 */
 
 
/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
 
  /** Configure the main internal regulator output voltage
  */
  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);
 
  /** 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_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 8;
  RCC_OscInitStruct.PLL.PLLN = 84;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  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_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  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_2) != HAL_OK)
  {
    Error_Handler();
  }
}
 
/**
  * @brief ADC1 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_ADC1_Init(void)
{
 
  /* USER CODE BEGIN ADC1_Init 0 */
 
  /* USER CODE END ADC1_Init 0 */
 
  ADC_ChannelConfTypeDef sConfig = {0};
 
  /* USER CODE BEGIN ADC1_Init 1 */
 
  /* USER CODE END ADC1_Init 1 */
 
  /** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
  */
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.ScanConvMode = DISABLE;
  hadc1.Init.ContinuousConvMode = DISABLE;
  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 = 1;
  hadc1.Init.DMAContinuousRequests = DISABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** 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_3CYCLES;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN ADC1_Init 2 */
 
  /* USER CODE END ADC1_Init 2 */
 
}
 
/**
  * @brief GPIO Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
 
  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOA_CLK_ENABLE();
 
}
 
/* USER CODE BEGIN 4 */
 
/* USER CODE END 4 */
 
/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}
 
#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 */
 
To check if these value changes, I used "Live Expressions" and could get "ADC" value, but " v " couldn't.

Recently I have started to learn programming, so I'm just a beginner.

If you have any idea, please teach me.

1 ACCEPTED SOLUTION

Accepted Solutions

Hello @MED2972 ,

To solve the issue and to get the voltage value. I suggest that you declare v just after __IO uint32_t ADC.

/* USER CODE BEGIN PV */
__IO uint32_t ADC;
double v;
/* USER CODE END PV */
Thanks.
Mahmoud.

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

View solution in original post

14 REPLIES 14
Mahmoud Ben Romdhane
ST Employee

Hello @MED2972,

First let me thank you for posting and welcome to the ST Community.

I advise you to consult this wiki provided by ST. It explains what ADC is and how to use it through an example.

Thanks.

Mahmoud.

 

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

I can watch ADC value on Live Expression, so I can do AD converting.

What I want to know is to calculate from " ADC " value to " v " value.

Could you teach me how to do that?

 

Hello @MED29722972,

Could you please provide your IOC file.

Thanks.

Mahmoud

 

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

MED2972
Associate III

Sorry to keep you waiting.

I also don't know how to give you IOC file.

Could you tell me how?

Hello @MED2972 ,

Further to your comment, I suggest that you add your project to a zip file and load it into ST community.

Thanks.

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

I made a zip file, but I don't know how to send.

What should I do?

I don't know much about PC.

Mahmoud Ben Romdhane
ST Employee

Hello @MED2972,

You should click on browse and select the zip file.

 

MahmoudBenRomdhane_1-1697703412211.png

Thanks.

 

 

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

I tried to put the zip file, but this caution popped up.

The file type (.zip) is not supported. Valid file types are: ai, avi, bmp, csv, doc, docx, flv, gif, ico, jpg, jpeg, log, mov, mpg, mpeg, mp3, odt, odp, ods, pdf, png, pps, ppt, pptx, rar, rm, tif, tiff, txt, xlr, xls, xlsx, xml, wmv, wav, z, 7z, ioc, hex, c, cc, cpp, h, hpp, tar, xz, dts.

 

Hello @MED2972 ,

I suggest that you load the file .ioc because the maximum Zip File size which you can share is 5 MB.

Thanks.

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.