system_stm32f0xx.h(基于v1.2.1)

【system_stm32f0xx.h(基于v1.2.1)】extern uint32_t SystemCoreClock;
extern void SystemInit(void);
extern void SystemCoreClockUpdate(void);
+++++++END++++++++
system_stm32f0xx.c SystemInit();
SystemCoreClock
SystemCoreClockUpdate();

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