/**
??******************************************************************************
??*?@file????system_stm32f0xx.c
??*?@author??MCD?Application?Team
??*?@version?V1.3.1
??*?@date????17-January-2014
??*?@brief???CMSIS?Cortex-M0?Device?Peripheral?Access?layer?System?Source?File.
??*??????????This?file?contains?the?system?clock?configuration?for?STM32F0xx?devices
??*??????????and?is?generated?by?the?clock?configuration?tool??
??*??????????STM32F0xx_Clock_Configuration_V1.0.0.xls
??*
??*?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_stm32f0xx.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?（8?MHz?Range）?is?used?as?system?clock?source.
??*????Then?SystemInit（）?function?is?called?in?“startup_stm32f0xx.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?8MHz?refer?to?“HSE_VALUE“?define
??*????in?“stm32f0xx.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:
??*=============================================================================
??*?????????????????????????System?Clock?Configuration
??*=============================================================================
??*????????System?Clock?source??????????|?PLL（HSE）
??*-----------------------------------------------------------------------------
??*????????SYSCLK???????????????????????|?48000000?Hz
??*-----------------------------------------------------------------------------
??*????????HCLK?????????????????????????|?48000000?Hz
??*---------------

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-09-13?13:36??Libraries\
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\include\
?????文件??????240326??2014-12-13?22:42??Libraries\CMSIS\include\arm_math.h
?????文件???????31948??2014-12-13?22:42??Libraries\CMSIS\include\core_cm0.h
?????文件???????15691??2014-12-13?22:42??Libraries\CMSIS\include\core_cmFunc.h
?????文件???????16108??2014-12-13?22:42??Libraries\CMSIS\include\core_cmInstr.h
?????文件??????410939??2014-12-22?22:48??Libraries\CMSIS\include\stm32f0xx.h
?????文件????????2222??2014-12-13?22:42??Libraries\CMSIS\include\system_stm32f0xx.h
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\source\
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\source\startup\
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\source\startup\arm\
?????文件???????10068??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f030.s
?????文件????????9866??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f031.s
?????文件???????10703??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f042.s
?????文件???????10703??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f051.s
?????文件???????11163??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f072.s
?????文件???????10703??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f0xx.s
?????文件????????9870??2014-12-13?22:42??Libraries\CMSIS\source\startup\arm\startup_stm32f0xx_ld.s
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\source\startup\gcc_ride7\
?????文件????????8237??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f030.s
?????文件????????8057??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f031.s
?????文件????????8577??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f042.s
?????文件????????8677??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f051.s
?????文件????????9013??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f072.s
?????文件????????8670??2014-12-13?22:42??Libraries\CMSIS\source\startup\gcc_ride7\startup_stm32f0xx.s
?????目錄???????????0??2018-09-13?13:36??Libraries\CMSIS\source\startup\iar\
?????文件???????10333??2014-12-13?22:42??Libraries\CMSIS\source\startup\iar\startup_stm32f030.s
?????文件???????10071??2014-12-13?22:42??Libraries\CMSIS\source\startup\iar\startup_stm32f031.s
?????文件???????10902??2014-12-13?22:42??Libraries\CMSIS\source\startup\iar\startup_stm32f042.s
?????文件???????11340??2014-12-13?22:42??Libraries\CMSIS\source\startup\iar\startup_stm32f051.s
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