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Heinrich
Associate III
October 11, 2024
Solved

NUCLEO-G431KB, wrong values on ADC channel 4

  • October 11, 2024
  • 11 replies
  • 3259 views

Hello Forum,

I have an issue while reading the values from ADC. ADC1 is running in "continues scan convertion mode" using DMA and 5 ranks.

Here is ADC_Init function:

static void MX_ADC1_Init(void)
{

 /* USER CODE BEGIN ADC1_Init 0 */

 /* USER CODE END ADC1_Init 0 */

 ADC_MultiModeTypeDef multimode = {0};
 ADC_ChannelConfTypeDef sConfig = {0};

 /* USER CODE BEGIN ADC1_Init 1 */

 /* USER CODE END ADC1_Init 1 */

 /** Common config
 */
 hadc1.Instance = ADC1;
 hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
 hadc1.Init.Resolution = ADC_RESOLUTION_12B;
 hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
 hadc1.Init.GainCompensation = 0;
 hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
 hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
 hadc1.Init.LowPowerAutoWait = DISABLE;
 hadc1.Init.ContinuousConvMode = ENABLE;
 hadc1.Init.NbrOfConversion = 5;
 hadc1.Init.DiscontinuousConvMode = DISABLE;
 hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
 hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
 hadc1.Init.DMAContinuousRequests = ENABLE;
 hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
 hadc1.Init.OversamplingMode = DISABLE;
 if (HAL_ADC_Init(&hadc1) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure the ADC multi-mode
 */
 multimode.Mode = ADC_MODE_INDEPENDENT;
 if (HAL_ADCEx_MultiModeConfigChannel(&hadc1, &multimode) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_TEMPSENSOR_ADC1;
 sConfig.Rank = ADC_REGULAR_RANK_1;
 sConfig.SamplingTime = ADC_SAMPLETIME_247CYCLES_5;
 sConfig.SingleDiff = ADC_SINGLE_ENDED;
 sConfig.OffsetNumber = ADC_OFFSET_NONE;
 sConfig.Offset = 0;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_VREFINT;
 sConfig.Rank = ADC_REGULAR_RANK_2;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_1;
 sConfig.Rank = ADC_REGULAR_RANK_3;
 sConfig.SamplingTime = ADC_SAMPLETIME_24CYCLES_5;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_2;
 sConfig.Rank = ADC_REGULAR_RANK_4;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_4;
 sConfig.Rank = ADC_REGULAR_RANK_5;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN ADC1_Init 2 */

 /* USER CODE END ADC1_Init 2 */

}

Then, here is my main() function:

int main(void)
{

 /* USER CODE BEGIN 1 */


 /* 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_DMA_Init();
 MX_DAC1_Init();
 MX_I2C2_Init();
 MX_USB_Device_Init();
 MX_TIM17_Init();
 MX_CRC_Init();
 MX_ADC1_Init();
 /* USER CODE BEGIN 2 */
 if (HAL_ADCEx_Calibration_Start(&hadc1, ADC_SINGLE_ENDED) != HAL_OK)
 {
	 Error_Handler();
 }

 if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *) &adc_convertions, 5) != HAL_OK)
 {
	 Error_Handler();
 }



 HAL_DAC_Start(&hdac1, DAC1_CHANNEL_1);
 HAL_DAC_Start(&hdac1, DAC1_CHANNEL_2);
 HAL_TIM_Base_Start_IT(&htim17);

 AT24CXX_Init(hi2c2);
 load_configuration();
 init_spline();
 // load_default_configuration();

 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
	 timer_tasks_execute();

	 if (received_data)
	 {
		 process_tunerstudio();
		 received_data = false;
	 }
 /* USER CODE END WHILE */

 /* USER CODE BEGIN 3 */
 }
 /* USER CODE END 3 */
}

The variable adc_convertions is declared as uint32_t adc_convertions[5] = {0};

Issue:

If I apply the a voltage (2.15v) to PA1 and PA3, in adc_convertions array I get the ADC of 2620 for PA1 and 1531 for PA3. But, the both values shold be equal... The another ranks in adc_convertions array are correct.

  • I've tried to change a sample time for CHANNEL4 (= PA3), no success.
  • I removed SB1 and SB12 (because PA3 is connected to STLINK-V3E virtual c omport) , no success.
  • I've tried to map CHANNEL4 to different Rank, no success.

So, 'Ive no idea anymore...

Can you please help me?

Many thanks & regards,
Heinrich

This topic has been closed for replies.
Best answer by waclawek.jan

> If I apply the a voltage (2.15v) to PA1 and PA3

So, are PA1 and PA3 physically connected together?

> I removed SB1 and SB12 (because PA3 is connected to STLINK-V3E virtual c omport)

And did you connect SB14?

JW

11 replies

Karl Yamashita
Principal
October 11, 2024

Change your type to uint16_t instead of uint32_t 

 

If a reply has proven helpful, click on Accept as Solution so that it'll show at top of the post.CAN Jammer an open source CAN bus hacking toolCANableV3 Open Source
Heinrich
HeinrichAuthor
Associate III
October 11, 2024

Do you mean the type of adc_convertions[5]?

Regards,
Heinrich

MM..1
Super User
October 12, 2024

Yes ADC is 12bit then optimal result is 16bit half word DMA and uint16_t array.

And for addressing array right syntax is adc_convertions or &adc_convertions[0] .

MasterT
Lead II
October 11, 2024

Instead:

if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *) &adc_convertions, 5) != HAL_OK)

try:

if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *)  adc_convertions, 5) != HAL_OK)

 

And declaration of : uint32_t adc_convertions[5] = {0}; depends on DMA_word size, what we can't see, since no dma config provided.

waclawek.jan
waclawek.janBest answer
Super User
October 12, 2024

> If I apply the a voltage (2.15v) to PA1 and PA3

So, are PA1 and PA3 physically connected together?

> I removed SB1 and SB12 (because PA3 is connected to STLINK-V3E virtual c omport)

And did you connect SB14?

JW

Heinrich
HeinrichAuthor
Associate III
October 12, 2024

Hi guys, first of all, thank you very much for help :)

@MasterT:

DMA is configured like this at the moment:

Heinrich_0-1728739610358.png

Since STM32 is a 32-bit MCU, WORD means uint32_t, I think... It is correct?

@waclawek.jan 

Yes, PA1 and PA3 are connected together. Not directly on Nucleo, but on carrier board. The is a voltage divider (5v to 3.3), then buffer and then NUCLEO. AI've applied 3.3v from NUCLEO to both input pins, after voltage diviers and buffers, I get 2.15v on BOTH pins of NUCLEO. So, the hardware should be okay, because the get the same voltage.

No, SB15 is still default, so not "installed".

@MM..1Okay, I've removed & , the DMA is configured as word, not half-word.

What I've done:

  • Remove the & in if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *) adc_convertions, 5) != HAL_OK)
  • Changed uint32_t to uint16_t.

Result:

  • CHANNEL1 (adc_convertions[0]) says 2620, correct.
  • CHANNEL4 (adc_convertions[1]) says 0, normal since SB14 is open...

I will close SB14 a bit later and test it :)

MasterT
Lead II
October 12, 2024

If DMA configured as Word_Peripheral- Word_Memory, than 

uint32_t adc_convertions[5] = {0};  or int32_t adc_convertions[5] = {0};

correct declaration. 

For Halfword_Peripheral- Halfword_Memory, than 

uint16_t adc_convertions[5] = {0};  or int16_t adc_convertions[5] = {0}; 

Heinrich
HeinrichAuthor
Associate III
October 12, 2024

Okay, then it was correct.

I've changed them back to uint32_t adc_convertions[5] = {0};

and:

  • adc_convertions[0] says 2621, correct
  • adc_convertions[1] says 1543, wrong

I'll test with SB14 closed today evening.

Regards,
Heinrich

Heinrich
HeinrichAuthor
Associate III
October 12, 2024

So, now I've closed SB14 and started a new project, adc + dma only.

DMA Config:

Heinrich_0-1728751558532.png

With buffer for DMA data:

 

uint16_t adc_values[2] = {0};

 

And DMA start:

 

 if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *) adc_values, 2) != HAL_OK)
 {
	 Error_Handler();
 }

 

ADC config:

Heinrich_1-1728751603109.png

ADC config 2nd:

Heinrich_2-1728751629736.png

Here is the whole code from main.c:

 

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2024 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;
DMA_HandleTypeDef hdma_adc1;

/* USER CODE BEGIN PV */

uint16_t adc_values[2] = {0};

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_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 */

 /* 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_DMA_Init();
 MX_ADC1_Init();
 /* USER CODE BEGIN 2 */
 if (HAL_ADC_Start_DMA(&hadc1, (uint32_t *) adc_values, 2) != HAL_OK)
 {
	 Error_Handler();
 }

 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */

 uint32_t blah = 0;
 while (1)
 {
	 HAL_Delay(500);
	 blah++;
 /* USER CODE END WHILE */

 /* USER CODE BEGIN 3 */
 }
 /* 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_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);

 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV2;
 RCC_OscInitStruct.PLL.PLLN = 24;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
 RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
 RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
 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_DIV1;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != 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_MultiModeTypeDef multimode = {0};
 ADC_ChannelConfTypeDef sConfig = {0};

 /* USER CODE BEGIN ADC1_Init 1 */

 /* USER CODE END ADC1_Init 1 */

 /** Common config
 */
 hadc1.Instance = ADC1;
 hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
 hadc1.Init.Resolution = ADC_RESOLUTION_12B;
 hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
 hadc1.Init.GainCompensation = 0;
 hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
 hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
 hadc1.Init.LowPowerAutoWait = DISABLE;
 hadc1.Init.ContinuousConvMode = ENABLE;
 hadc1.Init.NbrOfConversion = 2;
 hadc1.Init.DiscontinuousConvMode = DISABLE;
 hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
 hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
 hadc1.Init.DMAContinuousRequests = ENABLE;
 hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
 hadc1.Init.OversamplingMode = DISABLE;
 if (HAL_ADC_Init(&hadc1) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure the ADC multi-mode
 */
 multimode.Mode = ADC_MODE_INDEPENDENT;
 if (HAL_ADCEx_MultiModeConfigChannel(&hadc1, &multimode) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_2;
 sConfig.Rank = ADC_REGULAR_RANK_1;
 sConfig.SamplingTime = ADC_SAMPLETIME_24CYCLES_5;
 sConfig.SingleDiff = ADC_SINGLE_ENDED;
 sConfig.OffsetNumber = ADC_OFFSET_NONE;
 sConfig.Offset = 0;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_4;
 sConfig.Rank = ADC_REGULAR_RANK_2;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN ADC1_Init 2 */
 if (HAL_ADCEx_Calibration_Start(&hadc1, ADC_SINGLE_ENDED) != HAL_OK)
 {
	 Error_Handler();
 }

 /* USER CODE END ADC1_Init 2 */

}

/**
 * Enable DMA controller clock
 */
static void MX_DMA_Init(void)
{

 /* DMA controller clock enable */
 __HAL_RCC_DMAMUX1_CLK_ENABLE();
 __HAL_RCC_DMA1_CLK_ENABLE();

 /* DMA interrupt init */
 /* DMA1_Channel1_IRQn interrupt configuration */
 HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);

}

/**
 * @brief GPIO Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOF_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOB_CLK_ENABLE();

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin : LD2_Pin */
 GPIO_InitStruct.Pin = LD2_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(LD2_GPIO_Port, &GPIO_InitStruct);

/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}

/* 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 */

 

Result:

  • adc_convertions[0] says 2622, correct
  • adc_convertions[1] says 2621, correct

I think the point with SB14 was the solution...

Now it fine and all the values are correct.

Thank you very much!