/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    Examples_LL/UTILS/UTILS_ConfigureSystemClock/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to configure system clock using PLL with
  *          HSI as source clock through the STM32WLxx UTILS 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 */
/* Variable to store PLL parameters */
/* Configuration will allow to reach a SYSCLK frequency set to 24MHz:
   Syst freq = ((HSI_VALUE / PLLM) * PLLN)/ PLLR)
               ((16MHz     /  1  ) *   6  /  4  ) = 24MHz            */
LL_UTILS_PLLInitTypeDef sUTILS_PLLInitStruct = {LL_RCC_PLLM_DIV_1, 6, LL_RCC_PLLR_DIV_4};


/* Variable to store AHB and APB buses clock configuration */
/* Settings to have HCLK1 set to 48MHz, APB1 to 12MHz and APB2 to 24MHz */
LL_UTILS_ClkInitTypeDef sUTILS_ClkInitStruct = {LL_RCC_SYSCLK_DIV_1, LL_RCC_APB1_DIV_4, LL_RCC_APB2_DIV_2};


/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
void     LED_Init(void);
void     MCO_ConfigGPIO(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 */
  /* System started with default clock used after reset */
  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  /* USER CODE BEGIN 2 */

  /* Switch to PLL with HSI as clock source             */
  LL_PLL_ConfigSystemClock_HSI(&sUTILS_PLLInitStruct, &sUTILS_ClkInitStruct);

  /*
     CMSIS variable automatically updated according to new configuration.
     SystemCoreClock should be equal to calculated HCLK frequency.
     FLASH latency is also tuned according to system constraints described
     in the reference manual.
  */

  /* Set Systick to 1ms in using frequency set to SystemCoreClock */
  LL_Init1msTick(SystemCoreClock);

  /* Initialize LED2 */
  LED_Init();

  /* Configure SYSCLK for MCO */
  MCO_ConfigGPIO();
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);
    LL_mDelay(1000);

    /* 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);
}

/* USER CODE BEGIN 4 */

/**
  * @brief  Initialize LED2.
  * @param  None
  * @retval None
  */
void LED_Init(void)
{
  /* Enable the LED2 Clock */
  LED2_GPIO_CLK_ENABLE();

  /* Configure IO in output push-pull mode to drive external LED2 */
  LL_GPIO_SetPinMode(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_MODE_OUTPUT);
  /* Reset value is LL_GPIO_OUTPUT_PUSHPULL */
  //LL_GPIO_SetPinOutputType(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_OUTPUT_PUSHPULL);
  /* Reset value is LL_GPIO_SPEED_FREQ_LOW */
  //LL_GPIO_SetPinSpeed(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_SPEED_FREQ_LOW);
  /* Reset value is LL_GPIO_PULL_NO */
  //LL_GPIO_SetPinPull(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_PULL_NO);

  /* Select MCO clock source and prescaler */
  LL_RCC_ConfigMCO(LL_RCC_MCO1SOURCE_SYSCLK, LL_RCC_MCO1_DIV_1);
}

/**
  * @brief  Configure MCO pin (PA8).
  * @param  None
  * @retval None
  */
void MCO_ConfigGPIO(void)
{
  /* MCO Clock Enable */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);

  /* Configure the MCO pin in alternate function mode */
  LL_GPIO_SetPinMode(GPIOA, LL_GPIO_PIN_8, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetPinOutputType(GPIOA, LL_GPIO_PIN_8, LL_GPIO_OUTPUT_PUSHPULL);
  LL_GPIO_SetPinSpeed(GPIOA, LL_GPIO_PIN_8, LL_GPIO_SPEED_FREQ_VERY_HIGH);
  LL_GPIO_SetPinPull(GPIOA, LL_GPIO_PIN_8, LL_GPIO_PULL_NO);
  LL_GPIO_SetAFPin_8_15(GPIOA, LL_GPIO_PIN_8, LL_GPIO_AF_0);
}

/* 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 */
