Hi im working on stm32l072cbt6 micro controller im trying to read the adc value on channel1 in polling method i generated the code using stm32 cube ide,the issue is that always i could not se any variation in the adc raw values and my code is as below,

[NJP.1]

void MX_ADC_Init(void)
{
 
  /* USER CODE BEGIN ADC_Init 0 */
 
  /* USER CODE END ADC_Init 0 */
 
  ADC_ChannelConfTypeDef sConfig = {0};
 
  /* USER CODE BEGIN ADC_Init 1 */
 
  /* USER CODE END ADC_Init 1 */
  /** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
  */
  hadc.Instance = ADC1;
  hadc.Init.OversamplingMode = DISABLE;
  hadc.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;
  hadc.Init.Resolution = ADC_RESOLUTION_12B;
  hadc.Init.SamplingTime = ADC_SAMPLETIME_1CYCLE_5;
  hadc.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD;
  hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc.Init.ContinuousConvMode = DISABLE;
  hadc.Init.DiscontinuousConvMode = DISABLE;
  hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc.Init.DMAContinuousRequests = DISABLE;
  hadc.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  hadc.Init.Overrun = ADC_OVR_DATA_PRESERVED;
  hadc.Init.LowPowerAutoWait = DISABLE;
  hadc.Init.LowPowerFrequencyMode = DISABLE;
  hadc.Init.LowPowerAutoPowerOff = DISABLE;
  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;
  if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN ADC_Init 2 */
 
  /* USER CODE END ADC_Init 2 */
 
}
 
void HAL_ADC_MspInit(ADC_HandleTypeDef* adcHandle)
{
 
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(adcHandle->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspInit 0 */
 
  /* USER CODE END ADC1_MspInit 0 */
    /* ADC1 clock enable */
    __HAL_RCC_ADC1_CLK_ENABLE();
 
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**ADC GPIO Configuration
    PA0     ------> ADC_IN0
    */
    GPIO_InitStruct.Pin = GPIO_PIN_0;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
  /* USER CODE BEGIN ADC1_MspInit 1 */
 
  /* USER CODE END ADC1_MspInit 1 */
  }
}
 
 
 
 
 
main()
{
 HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
  MX_USART1_UART_Init();
  MX_USART2_UART_Init();
  MX_ADC_Init();
while(1)
{
      AD_RES = 0;
	  HAL_GPIO_WritePin(BUZZER_GPIO_Port, BUZZER_Pin, GPIO_PIN_RESET);
	  //HAL_UART_Transmit(&huart1, "HI\r\n", sizeof("HI\r\n"), 100);
	 // HAL_UART_Transmit(&huart2, "BYE\r\n", sizeof("HI\r\n"), 100);
	  HAL_ADC_Start(&hadc1);
	// Poll ADC1 Perihperal & TimeOut = 1mSec
	  HAL_ADC_PollForConversion(&hadc1, 1);
	 AD_RES = HAL_ADC_GetValue(&hadc1);
	 sprintf(Buf,"raw value adc1 %u\n\r", AD_RES);
	 HAL_UART_Transmit(&huart1,Buf, sizeof(Buf), 100);
	 HAL_Delay(100);
}
}

[TDK]

What value are you getting out?

Monitor the HAL_* functions to verify they are returning HAL_OK. If they are not, start your troubleshooting there.

[MM..1]

Set this aka input signal impedance

hadc.Init.SamplingTime = ADC_SAMPLETIME_1CYCLE_5;

[NJP.1]

Thankyou for the reply im getting 2801 constantly

"Monitor the HAL_* functions to verify they are returning HAL_OK. If they are not, start your troubleshooting there"

Ok i will check it out

[NJP.1]

Yes i have added this line in the code..

[MM..1]

You need change ADC_SAMPLETIME_1CYCLE_5
start with biggest

[NJP.1]

thankyou i have added the maximum of "hadc.Init.SamplingTime = ADC_SAMPLETIME_160CYCLES_5;" The code got hanged., And i have now got a code which is working with the single adc but for polling adc0,adc1,adc5,adc6 all together the channel is not changing im getting only one value for all the adc i have attached my new code below any thoughts on that please let me know

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 = 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 = 1;
	  hadc1.Init.DMAContinuousRequests = DISABLE;
	  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
	  //naga
	  hadc.Init.SamplingTime = ADC_SAMPLETIME_160CYCLES_5;
 
	  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_28CYCLES;
	//  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != 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_1;
	//  sConfig.Rank = 2;
	//  sConfig.SamplingTime = ADC_SAMPLETIME_84CYCLES;
	//  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != 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_TEMPSENSOR;
	//  sConfig.Rank = 3;
	//  sConfig.SamplingTime = ADC_SAMPLETIME_112CYCLES;
	//  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
	//  {
	//    Error_Handler();
	//  }
	  /* USER CODE BEGIN ADC1_Init 2 */
 
	  /* USER CODE END ADC1_Init 2 */
}
 
 
void ADC_Select_CH0 (void)
{
	ADC_ChannelConfTypeDef sConfig = {0};
	  /** 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_28CYCLES;
	  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
	  {
	    Error_Handler();
	  }
}
 
void ADC_Select_CH1 (void)
{
	ADC_ChannelConfTypeDef sConfig = {0};
	  /** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
	  */
	  sConfig.Channel = ADC_CHANNEL_1;
	  sConfig.Rank = 1;
	  //sConfig.SamplingTime = ADC_SAMPLETIME_84CYCLES;
	  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
	  {
	    Error_Handler();
	  }
}
 
void ADC_Select_CH5 (void)
{
	ADC_ChannelConfTypeDef sConfig = {0};
	  /** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
	  */
	  sConfig.Channel = ADC_CHANNEL_5;
	  sConfig.Rank = 1;
	  //sConfig.SamplingTime = ADC_SAMPLETIME_84CYCLES;
	  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
	  {
	    Error_Handler();
	  }
}
 
 while (1)
  {
	  AD_RES0 = 0;
	  AD_RES1 = 0;
 
	  HAL_GPIO_WritePin(BUZZER_GPIO_Port, BUZZER_Pin, GPIO_PIN_RESET);
	 
 
	      ADC_Select_CH0();
		  HAL_ADC_Start(&hadc1);
		  HAL_ADC_PollForConversion(&hadc1, 1000);
		  AD_RES0 = HAL_ADC_GetValue(&hadc1);
		  HAL_ADC_Stop(&hadc1);
		  sprintf(Buf,"adc0 %u  \r\n", AD_RES0);
		  HAL_UART_Transmit(&huart1,Buf, sizeof(Buf), 100);
		 HAL_Delay(100);
 
 
	  	 ADC_Select_CH1();
		  HAL_ADC_Start(&hadc1);
		  HAL_ADC_PollForConversion(&hadc1, 1000);
		  AD_RES1 = HAL_ADC_GetValue(&hadc1);
		  HAL_ADC_Stop(&hadc1);
		  sprintf(Buf," adc1 %u \r\n", AD_RES1);
		  HAL_UART_Transmit(&huart1,Buf, sizeof(Buf), 100);
		  HAL_Delay(100);
 
 
	 	ADC_Select_CH5();
		HAL_ADC_Start(&hadc1);
		HAL_ADC_PollForConversion(&hadc1, 1000);
		AD_RES5 = HAL_ADC_GetValue(&hadc1);
		HAL_ADC_Stop(&hadc1);
		sprintf(Buf,"adc5 %u\n\r", AD_RES5);
		HAL_UART_Transmit(&huart1,Buf, sizeof(Buf), 100);
		HAL_Delay(100);
}