/**
??******************************************************************************
??*?@file????system_stm32f4xx.c
??*?@author??MCD?Application?Team
??*?@version?V1.8.0
??*?@date????09-November-2016
??*?@brief???CMSIS?Cortex-M4?Device?Peripheral?Access?layer?System?Source?File.
??*??????????This?file?contains?the?system?clock?configuration?for?STM32F4xx?devices.
??*?????????????
??*?1.??This?file?provides?two?functions?and?one?global?variable?to?be?called?from?
??*?????user?application:
??*??????-?SystemInit（）:?Setups?the?system?clock?（System?clock?source?PLL?Multiplier
??*??????????????????????and?Divider?factors?AHB/APBx?prescalers?and?Flash?settings）
??*??????????????????????depending?on?the?configuration?made?in?the?clock?xls?tool.?
??*??????????????????????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.
??*
??*?2.?After?each?device?reset?the?HSI?（16?MHz）?is?used?as?system?clock?source.
??*????Then?SystemInit（）?function?is?called?in?“startup_stm32f4xx.s“?file?to
??*????configure?the?system?clock?before?to?branch?to?main?program.
??*
??*?3.?If?the?system?clock?source?selected?by?user?fails?to?startup?the?SystemInit（）
??*????function?will?do?nothing?and?HSI?still?used?as?system?clock?source.?User?can?
??*????add?some?code?to?deal?with?this?issue?inside?the?SetSysClock（）?function.
??*
??*?4.?The?default?value?of?HSE?crystal?is?set?to?25MHz?refer?to?“HSE_VALUE“?define
??*????in?“stm32f4xx.h“?file.?When?HSE?is?used?as?system?clock?source?directly?or
??*????through?PLL?and?you?are?using?different?crystal?you?have?to?adapt?the?HSE
??*????value?to?your?own?configuration.
??*
??*?5.?This?file?configures?the?system?clock?as?follows:
??*=============================================================================
??*=============================================================================
??*????????????????????Supported?STM32F40xxx/41xxx?devices
??*-----------------------------------------------------------------------------
??*????????System?Clock?source????????????????????|?PLL?（HSE）
??*-----------------------------------------------------------------------------
??*????????SYSCLK（Hz）?????????????????????????????|?168000000
??*-----------------------------------------------------------------------------
??*????????HCLK（Hz）?????????????????????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????61020??2016-11-10?18:29??激光測距模塊簡易測量（STM32F429）\CMSIS\system_stm32f4xx.c

?????文件?????????29??2019-09-09?21:56??激光測距模塊簡易測量（STM32F429）\DOC\readme.txt

?????文件??????17016??2019-08-27?19:28??激光測距模塊簡易測量（STM32F429）\DOC\激光測距模塊圖片.jpg

?????文件??????56832??2019-08-09?16:37??激光測距模塊簡易測量（STM32F429）\DOC\激光測距模塊通訊協議.doc

?????文件??????25819??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f401xx.s

?????文件??????29696??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f40xx.s

?????文件??????29607??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f40_41xxx.s

?????文件??????19189??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f410xx.s

?????文件??????26519??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f411xe.s

?????文件??????21484??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f412xg.s

?????文件??????23401??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f413_423xx.s

?????文件??????31056??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f427x.s

?????文件??????30981??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f427_437xx.s

?????文件??????31136??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f429_439xx.s

?????文件??????22148??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f446xx.s

?????文件??????30929??2016-11-07?23:02??激光測距模塊簡易測量（STM32F429）\LIBRARIES\ARM\startup_stm32f469_479xx.s

?????文件???????7253??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\arm_common_tables.h

?????文件???????3942??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\arm_const_structs.h

?????文件?????252177??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\arm_math.h

?????文件??????36181??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cm0.h

?????文件??????43812??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cm0plus.h

?????文件?????103865??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cm3.h

?????文件?????114403??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cm4.h

?????文件?????138654??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cm7.h

?????文件??????18323??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cmFunc.h

?????文件??????27908??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cmInstr.h

?????文件??????22947??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_cmSimd.h

?????文件??????44330??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_sc000.h

?????文件?????102775??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\Core\core_sc300.h

?????文件???????6926??2016-11-05?01:33??激光測距模塊簡易測量（STM32F429）\LIBRARIES\inc\misc.h

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