ADC in low power run mode measure same numbers - c

Question

I have stm32L053R8 nucleo64 board. I'm trying to get adc measure in low power run mode. It's not working correctly in Lprun mode but when I try in run mode it's working. In Lprun mode I only get 2 values. Half of the resolution and full of the resolution(12bit -> 2047 & 4095). Can you guys help me to figure out where am I doing wrong?
I tried to figure out why this happens and configured LFMEN, VREFEN, ULP bits but didn't worked.
ADC_HandleTypeDef hadc;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_ADC_Init(void);
uint16_t adcVal = 0;
int main(void) {
HAL_Init();
MX_GPIO_Init();
MX_ADC_Init();
/*
// Bit 25 LFMEN: Low Frequency Mode enabled
ADC->CCR |= (1UL << 25);
// Bit 22 VREFEN: VREFINT enable
ADC->CCR |= (1UL << 22);
// Bit 9 ULP: Vrefint is ON in low power mode
PWR->CR &= ~(1UL << 9U);
*/
HAL_PWREx_EnableLowPowerRunMode();
while (1) {
HAL_Delay(500);
HAL_ADC_Start(&hadc);
HAL_ADC_PollForConversion(&hadc, 100);
adcVal = HAL_ADC_GetValue(&hadc);
HAL_ADC_Stop(&hadc);
}
}
/* #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_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
/* Initializes the RCC Oscillators according to the specified
*parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_ON;
RCC_OscInitStruct.MSICalibrationValue = 0;
RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_2;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
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_MSI;
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_0) != HAL_OK) {
Error_Handler();
}
}
/*
* #brief ADC Initialization Function
* #param None
* #retval None
*/
static 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_DIV1;
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 = ENABLE;
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_1;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK) {
Error_Handler();
}
}