/** ****************************************************************************** * @file system_stm32f4xx.c * @author MCD Application Team * @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 * *

© COPYRIGHT 2017 STMicroelectronics

* * 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. * ****************************************************************************** */ /** * @file system_init.c * @brief support SystemInit function * @version 1.0 * @author AIIT XUOS Lab * @date 2021-04-29 */ /************************************************* File name: system_init.c Description: support SystemInit function Others: History: 1. Date: 2021-04-29 Author: AIIT XUOS Lab Modification: 1. take system_stm32f4xx.c for XiUOS *************************************************/ #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 */ #define VECT_TAB_OFFSET 0x00 void SystemInit(void) { SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); RCC->CR |= (uint32_t)0x00000001; RCC->CFGR = 0x00000000; RCC->CR &= (uint32_t)0xFEF6FFFF; RCC->PLLCFGR = 0x24003010; RCC->CR &= (uint32_t)0xFFFBFFFF; RCC->CIR = 0x00000000; #if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM) SystemInitExtMemCtl(); #endif #ifdef VECT_TAB_SRAM SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; #else SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; #endif }