/**
  ******************************************************************************
  * @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 STM32F1xx UTILS LL API.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2016 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.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/** @addtogroup STM32F1xx_LL_Examples
  * @{
  */

/** @addtogroup UTILS_ConfigureSystemClock
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Variable to store PLL parameters */
/* Configuration will allow to reach a SYSCLK frequency set to 64MHz: 
   Syst freq = ((HSI_VALUE / LL_RCC_PLLSOURCE_HSI_DIV_2) * LL_RCC_PLL_MUL_16)
               ((8MHz /2) * 16)             = 64MHz                     */
LL_UTILS_PLLInitTypeDef sUTILS_PLLInitStruct = {LL_RCC_PLL_MUL_16, LL_RCC_PREDIV_DIV_1};

/* Variable to store AHB and APB buses clock configuration */
/* Settings to have HCLK set to 64MHz, APB1 to 32MHz and APB2 to 64MHz */
LL_UTILS_ClkInitTypeDef sUTILS_ClkInitStruct = {LL_RCC_SYSCLK_DIV_1, LL_RCC_APB1_DIV_2, LL_RCC_APB2_DIV_1};

/* Private function prototypes -----------------------------------------------*/
void     LED_Init(void);
void     MCO_ConfigGPIO(void);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  /* System started with default clock used after reset */
  /* Set FLASH latency */
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_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();

  /* Toggle LED2 in an infinite loop with a period of 1Hz */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);  
    LL_mDelay(1000);
  }
}

/**
  * @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);
}

/**
  * @brief  Configure MCO pin (PA8).
  * @param  None
  * @retval None
  */
void MCO_ConfigGPIO(void)
{
  /* MCO Clock Enable */
  LL_APB2_GRP1_EnableClock(LL_APB2_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_HIGH);

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

#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 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)
  {
  }
}
#endif

/**
  * @}
  */

/**
  * @}
  */