STM32F103 72MHz时钟设置

将系统时钟初始化到72MHz的函数

1. 这是.c文件

#include "clock.h"

void Set_SysClockTo72M(void)
{
unsigned int faultTime = 0;
unsigned int rccCrHserdy = 0;
unsigned int rccCrPLLrdy = 0;

rRCC_CR = RCC_CR_RESET;
rRCC_CR &= ~(1<<16);
rRCC_CR |= (1<<16);

do
{
rccCrHserdy = rRCC_CR & (1<<17);
faultTime++;
}
while ((faultTime<0x0FFFFFFF) && (rccCrHserdy==0));

if ((rRCC_CR & (1<<17)) != 0)
{
rFLASH_ACR |= 0x10;
rFLASH_ACR &= (~0x03);
rFLASH_ACR |= 0x02;

rRCC_CFGR &= (~((0x0F<<4) | (0x07<<8) | (0x07<<11)));
rRCC_CFGR |= ((0x0<<4) | (0x04<<8) | (0x0<<11));
rRCC_CFGR &= (~((0x01<<16) | (0x1<<17)));
rRCC_CFGR |= ((0x01<<16) | (0x0<<17));
rRCC_CFGR &= (~(0x0f<<18));
rRCC_CFGR |= (0x07<<18);
rRCC_CR 	|= (0x01<<24);

faultTime = 0;
do
{
rccCrPLLrdy = rRCC_CR & (1<<25);
faultTime++;
}
while ((faultTime<0x0FFFFFFF) && (rccCrPLLrdy==0));

if ((rRCC_CR & (1<<25)) == (1<<25))
{
rRCC_CFGR &= (~(0x03<<0));
rRCC_CFGR |= (0x02<<0);

faultTime = 0;
do
{
rccCrPLLrdy = rRCC_CFGR & (0x03<<2);
faultTime++;
}
while ((faultTime<0x0FFFFFFF) && (rccCrPLLrdy!=(0x02<<2)));

if(rRCC_CFGR & (0x03<<2))
{
}
else
{
while(1);
}
}
else
{
while(1);
}
}
else
{
while(1);
}
}

1. 这是.h文件

#ifndef __CLOCK_H__
#define __CLOCK_H__

#define FLASH_ACR	0x40022000
#define RCC_BASE	0x40021000
#define RCC_CR		(RCC_BASE + 0x00)
#define RCC_CFGR	(RCC_BASE + 0x04)

#define rRCC_CR		(*((volatile unsigned int *)RCC_CR))
#define rRCC_CFGR	(*((volatile unsigned int *)RCC_CFGR))
#define rFLASH_ACR	(*((volatile unsigned int *)FLASH_ACR))

#define RCC_CR_RESET  (0x00000083)

void Set_SysClockTo72M(void);

#endif

（为什么无法正常显示keil文件的中文注释…）