STM32F107的时钟设置由25M修改成8M

1.首先找到stm32f10x.h， system_stm32f10x.c这两个文件；

2. system_stm32f10x.c修改

#if defined (STM32F10X_LD_VL) || (defined STM32F10X_MD_VL)

#define SYSCLK_FREQ_HSE HSE_Value

/*#define SYSCLK_FREQ_24MHz 24000000 */

#else

/* #define SYSCLK_FREQ_HSE HSE_Value */

/* #define SYSCLK_FREQ_24MHz 24000000 */

/* #define SYSCLK_FREQ_36MHz 36000000 */

/* #define SYSCLK_FREQ_48MHz 48000000 */

/* #define SYSCLK_FREQ_56MHz 56000000 */

//#define SYSCLK_FREQ_72MHz 72000000

#endif

3.stm32f10x.h修改

#if !defined HSE_VALUE

#ifdef STM32F10X_CL

#define HSE_VALUE ((uint32_t)8000000) /*!< Value of the External oscillator in Hz */

#else

#define HSE_VALUE ((uint32_t)8000000) /*!< Value of the External oscillator in Hz */

#endif /* STM32F10X_CL */

#endif /* HSE_VALUE */