STM32CubeF7/Projects/STM32F767ZI-Nucleo/Examples_LL/UTILS/UTILS_ConfigureSystemClock/Src/main.c

/**
  ******************************************************************************
  * @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 STM32F7xx UTILS LL API.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

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

/** @addtogroup STM32F7xx_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 216MHz: 
   Syst freq = ((HSI_VALUE / PLLM) * PLLN)/ PLLR)
               ((16MHz /8) * 216)/ 2)             = 216MHz             */
LL_UTILS_PLLInitTypeDef sUTILS_PLLInitStruct = {LL_RCC_PLLM_DIV_8, 216, LL_RCC_PLLP_DIV_2}; ;

/* Variable to store AHB and APB buses clock configuration */
/* Settings to have HCLK set to 108MHz, APB1 to 54MHz and APB2 to 108MHz */
LL_UTILS_ClkInitTypeDef sUTILS_ClkInitStruct = {LL_RCC_SYSCLK_DIV_2, LL_RCC_APB1_DIV_4, LL_RCC_APB2_DIV_2};

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

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

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  /* Enable the CPU Cache */
  CPU_CACHE_Enable();
  
  /* System started with default clock used after reset */
  /* Set FLASH latency */
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_7);

  /* Enable PWR clock */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);

  /* Activation OverDrive Mode */
  LL_PWR_EnableOverDriveMode();
  while(LL_PWR_IsActiveFlag_OD() != 1)
  {
  };

  /* Activation OverDrive Switching */
  LL_PWR_EnableOverDriveSwitching();
  while(LL_PWR_IsActiveFlag_ODSW() != 1)
  {
  };

  /* 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 LED1 */
  LED_Init();

  /* Configure SYSCLK for MCO */
  MCO_ConfigGPIO();

  /* Toggle LED1 in an infinite loop with a period of 1Hz */
  while (1)
  {
    LL_GPIO_TogglePin(LED1_GPIO_PORT, LED1_PIN);  
    LL_mDelay(1000);
  }
}

/**
  * @brief  Initialize LED1.
  * @param  None
  * @retval None
  */
void LED_Init(void)
{
  /* Enable the LED1 Clock */
  LED1_GPIO_CLK_ENABLE();

  /* Configure IO in output push-pull mode to drive external LED1 */
  LL_GPIO_SetPinMode(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_MODE_OUTPUT);
  /* Reset value is LL_GPIO_OUTPUT_PUSHPULL */
  //LL_GPIO_SetPinOutputType(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_OUTPUT_PUSHPULL);
  /* Reset value is LL_GPIO_SPEED_FREQ_LOW */
  //LL_GPIO_SetPinSpeed(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_SPEED_FREQ_LOW);
  /* Reset value is LL_GPIO_PULL_NO */
  //LL_GPIO_SetPinPull(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_PULL_NO);

  /* Select MCO clock source and prescaler */
  LL_RCC_ConfigMCO(LL_RCC_MCO1SOURCE_PLLCLK, LL_RCC_MCO1_DIV_4);
}

/**
  * @brief  Configure MCO pin (PA8).
  * @param  None
  * @retval None
  */
void MCO_ConfigGPIO(void)
{
  /* MCO Clock Enable */
  LL_AHB1_GRP1_EnableClock(LL_AHB1_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);
  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);
}

#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
/**
  * @brief  CPU L1-Cache enable.
  * @param  None
  * @retval None
  */
static void CPU_CACHE_Enable(void)
{
  /* Enable I-Cache */
  SCB_EnableICache();

  /* Enable D-Cache */
  SCB_EnableDCache();
}

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/