/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    Examples_LL/PWR/PWR_EnterStopMode/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to enter and exit the Stop 2 mode
  *          through the STM32WLxx PWR LL API.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2020 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 ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
/* USER CODE BEGIN PFP */

void     Configure_PWR(void);
void     LED_Off(void);
void     LED_Blinking_5s(void);
void     EnterStop2Mode(void);

/* 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. */

  /* System interrupt init*/
  NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);

  /* 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();
  /* USER CODE BEGIN 2 */


  /* Configure Power IP */
  Configure_PWR();

  /* Led blinking during 5s in RUN mode */
  LED_Blinking_5s();

  /* Switch OFF LED2 */
  LED_Off();

  /* Enter Stop 2 mode */
  EnterStop2Mode();

  /* Here Device is in Stop 2 mode */

  /* USER CODE END 2 */

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

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

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_0);
  while(LL_FLASH_GetLatency() != LL_FLASH_LATENCY_0)
  {
  }

  LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE2);
  LL_RCC_HSI_Enable();

   /* Wait till HSI is ready */
  while(LL_RCC_HSI_IsReady() != 1)
  {
  }

  LL_RCC_HSI_SetCalibTrimming(64);
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSI);

   /* Wait till System clock is ready */
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSI)
  {
  }

  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAHB3Prescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1);

  LL_Init1msTick(16000000);

  /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(16000000);
}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOB);

  /**/
  LL_GPIO_ResetOutputPin(LED2_GPIO_Port, LED2_Pin);

  /**/
  GPIO_InitStruct.Pin = LED2_Pin;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_OUTPUT;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  LL_GPIO_Init(LED2_GPIO_Port, &GPIO_InitStruct);

}

/* USER CODE BEGIN 4 */

/**
  * @brief  Turn-off LED2.
  * @param  None
  * @retval None
  */
void LED_Off(void)
{
  /* Turn LED2 off */
  LL_GPIO_ResetOutputPin(LED2_GPIO_Port, LED2_Pin);
}

/**
  * @brief  Set LED2 to Blinking mode during 5s.
  * @param  None

  * @retval None
  */
void LED_Blinking_5s(void)
{
  uint32_t i = 0;

  /* Toggle IO in during 5s (25*200ms) */
  for(i = 0; i < 25; i++)
  {
    LL_GPIO_TogglePin(LED2_GPIO_Port, LED2_Pin);  
    LL_mDelay(200);
  }
}

/**
  * @brief  Function to configure and initialize PWR IP.
  * @param  None
  * @retval None
  */
void Configure_PWR(void)
{
  /* Ensure that MSI is wake-up system clock */ 
  LL_RCC_SetClkAfterWakeFromStop(LL_RCC_STOP_WAKEUPCLOCK_MSI);
}

/**
  * @brief  Function to configure and enter in Stop 2 Mode.
  * @param  None
  * @retval None
  */
void EnterStop2Mode(void)
{
  LL_GPIO_InitTypeDef gpio_initstruct = {LL_GPIO_PIN_ALL, LL_GPIO_MODE_ANALOG, 
                                         LL_GPIO_SPEED_FREQ_HIGH, LL_GPIO_OUTPUT_PUSHPULL, 
                                         LL_GPIO_PULL_NO, LL_GPIO_AF_0};

  /* Set all GPIO in analog state to reduce power consumption,                */
  /* Note: Debug using ST-Link is not possible during the execution of this   */
  /*       example because communication between ST-link and the device       */
  /*       under test is done through UART. All GPIO pins are disabled (set   */
  /*       to analog input mode) including  UART I/O pins.                    */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA |
                            LL_AHB2_GRP1_PERIPH_GPIOB |
                            LL_AHB2_GRP1_PERIPH_GPIOC |
                            LL_AHB2_GRP1_PERIPH_GPIOH);

  LL_GPIO_Init(GPIOA, &gpio_initstruct);
  LL_GPIO_Init(GPIOB, &gpio_initstruct);
  LL_GPIO_Init(GPIOC, &gpio_initstruct);
  LL_GPIO_Init(GPIOH, &gpio_initstruct);

  LL_AHB2_GRP1_DisableClock(LL_AHB2_GRP1_PERIPH_GPIOA |
                            LL_AHB2_GRP1_PERIPH_GPIOB |
                            LL_AHB2_GRP1_PERIPH_GPIOC |
                            LL_AHB2_GRP1_PERIPH_GPIOH);

  /** Request to enter Stop 2 mode
    * Following procedure describe in STM32WLxx Reference Manual
    * See PWR part, section Low-power modes, Stop 2 mode
    */
  /* Set Stop 2 mode when CPU enters deepsleep */
  LL_PWR_SetPowerMode(LL_PWR_MODE_STOP2);
  
  /* Set SLEEPDEEP bit of Cortex System Control Register */
  LL_LPM_EnableDeepSleep();

  /* Request Wait For Interrupt */
  __WFI();
}

/* 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 */
 
  /* 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", file, line) */

  /* Infinite loop */
  while (1)
  {
  }

  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */