/**
******************************************************************************
* @file system_stm32f4xx.c
* @author MCD Application Team
* @version V2.5.0
* @date 22-April-2016
* @brief CMSIS Cortex-M4 Device Peripheral Access Layer System Source File.
*
* This file provides two functions and one global variable to be called from
* user application:
* - SystemInit(): This function is called at startup just after reset and
* before branch to main program. This call is made inside
* the "startup_stm32f4xx.s" file.
*
* - SystemCoreClock variable: Contains the core clock (HCLK), it can be used
* by the user application to setup the SysTick
* timer or configure other parameters.
*
* - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must
* be called whenever the core clock is changed
* during program execution.
*
*
******************************************************************************
* @attention
*
* <h2><center>© COPYRIGHT 2016 STMicroelectronics</center></h2>
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of STMicroelectronics nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************
*/
/** @addtogroup CMSIS
* @{
*/
/** @addtogroup stm32f4xx_system
* @{
*/
/** @addtogroup STM32F4xx_System_Private_Includes
* @{
*/
#include "stm32f4xx.h"
#if !defined (HSE_VALUE)
#define HSE_VALUE ((uint32_t)25000000) /*!< Default value of the External oscillator in Hz */
#endif /* HSE_VALUE */
#if !defined (HSI_VALUE)
#define HSI_VALUE ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/
#endif /* HSI_VALUE */
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Defines
* @{
*/
/************************* Miscellaneous Configuration ************************/
/*!< Uncomment the following line if you need to use external SRAM or SDRAM as data memory */
#if defined(STM32F405xx) || defined(STM32F415xx) || defined(STM32F407xx) || defined(STM32F417xx)\
|| defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx)\
|| defined(STM32F469xx) || defined(STM32F479xx) || defined(STM32F412Zx) || defined(STM32F412Vx)
/* #define DATA_IN_ExtSRAM */
#endif /* STM32F40xxx || STM32F41xxx || STM32F42xxx || STM32F43xxx || STM32F469xx || STM32F479xx ||\
STM32F412Zx || STM32F412Vx */
#if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx)\
|| defined(STM32F446xx) || defined(STM32F469xx) || defined(STM32F479xx)
/* #define DATA_IN_ExtSDRAM */
#endif /* STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx || STM32F446xx || STM32F469xx ||\
STM32F479xx */
/*!< Uncomment the following line if you need to relocate your vector Table in
Internal SRAM. */
/* #define VECT_TAB_SRAM */
#define VECT_TAB_OFFSET 0x00 /*!< Vector Table base offset field.
This value must be a multiple of 0x200. */
/******************************************************************************/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Macros
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Variables
* @{
*/
/* This variable is updated in three ways:
1) by calling CMSIS function SystemCoreClockUpdate()
2) by calling HAL API function HAL_RCC_GetHCLKFreq()
3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
Note: If you use this function to configure the system clock; then there
is no need to call the 2 first functions listed above, since SystemCoreClock
variable is updated automatically.
*/
uint32_t SystemCoreClock = 16000000;
const uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_FunctionPrototypes
* @{
*/
#if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM)
static void SystemInit_ExtMemCtl(void);
#endif /* DATA_IN_ExtSRAM || DATA_IN_ExtSDRAM */
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Functions
* @{
*/
/**
* @brief Setup the microcontroller system
* Initialize the FPU setting, vector table location and External memory
* configuration.
* @param None
* @retval None
*/
void SystemInit(void)
{
/* FPU settings ------------------------------------------------------------*/
#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */
#endif
/* Reset the RCC clock configuration to the default reset state ------------*/
/* Set HSION bit */
RCC->CR |= (uint32_t)0x00000001;
/* Reset CFGR register */
RCC->CFGR = 0x00000000;
/* Reset HSEON, CSSON and PLLON bits */
RCC->CR &= (uint32_t)0xFEF6FFFF;
/* Reset PLLCFGR register */
RCC->PLLCFGR = 0x24003010;
/* Reset HSEBYP bit */
RCC->CR &= (uint32_t)0xFFFBFFFF;
/* Disable all interrupts */
RCC->CIR = 0x00000000;
#if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM)
SystemInit_ExtMemCtl();
#endif /* DATA_IN_ExtSRAM || DATA_IN_ExtSDRAM */
/* Configure the Vector Table location add offset address ------------------*/
#ifdef VECT_TAB_SRAM
SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */
#else
SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH */
#endif
}
/**
* @brief Update SystemCoreClock variable according to Clock Register Values.
* The SystemCoreClock variable contains the core clock (HCLK), it can
* be used by the user application to setup the SysTick timer or configure
* other parameters.
*
* @note Each time the core clock (HCLK) changes, this function must be called
* to update SystemCoreClock variable value. Otherwise, any configuration
* based
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