STM32F10X_CL 默认时钟25M 如果外部上的是8M 在STM32F10X.h中更改HSE_VALUE值
#if !defined HSE_VALUE
#ifdef STM32F10X_CL
#define STM32F10X ((uint32_t)25000000) /*!< Value of the External oscillator in Hz */ //ĬÈÏ25000000
#else
#define HSE_VALUE ((uint32_t)8000000) /*!< Value of the External oscillator in Hz */
#endif /* STM32F10X_CL */
#endif /* HSE_VALUE */