#include "stm32f10x_lib.h"void RCC_cfg();
void TIMER_cfg();
void NVIC_cfg();
void GPIO_cfg();int main()
{RCC_cfg();NVIC_cfg();GPIO_cfg();TIMER_cfg();//开启定时器2TIM_Cmd(TIM2,ENABLE);while(1);
}void RCC_cfg()
{//定义错误状态变量ErrorStatus HSEStartUpStatus;//将RCC寄存器重新设置为默认值RCC_DeInit();//打开外部高速时钟晶振RCC_HSEConfig(RCC_HSE_ON);//等待外部高速时钟晶振工作HSEStartUpStatus = RCC_WaitForHSEStartUp();if(HSEStartUpStatus == SUCCESS){//设置AHB时钟(HCLK)为系统时钟RCC_HCLKConfig(RCC_SYSCLK_Div1);//设置高速AHB时钟(APB2)为HCLK时钟RCC_PCLK2Config(RCC_HCLK_Div1);//设置低速AHB时钟(APB1)为HCLK的2分频RCC_PCLK1Config(RCC_HCLK_Div2);//设置FLASH代码延时FLASH_SetLatency(FLASH_Latency_2);//使能预取指缓存FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);//设置PLL时钟，为HSE的9倍频 8MHz * 9 = 72MHzRCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);//使能PLLRCC_PLLCmd(ENABLE);//等待PLL准备就绪while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET); //设置PLL为系统时钟源RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);//判断PLL是否是系统时钟while(RCC_GetSYSCLKSource() != 0x08);} //允许TIM2的时钟RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);//允许GPIO的时钟RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
}void TIMER_cfg()
{TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;//重新将Timer设置为缺省值TIM_DeInit(TIM2);//采用内部时钟给TIM2提供时钟源TIM_InternalClockConfig(TIM2);//预分频系数为36000-1，这样计数器时钟为72MHz/36000 = 2kHzTIM_TimeBaseStructure.TIM_Prescaler = 36000 - 1;//设置时钟分割TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;//设置计数器模式为向上计数模式TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//设置计数溢出大小，每计2000个数就产生一个更新事件TIM_TimeBaseStructure.TIM_Period = 2000 - 1;//将配置应用到TIM2中TIM_TimeBaseInit(TIM2,&TIM_TimeBaseStructure);//清除溢出中断标志TIM_ClearFlag(TIM2, TIM_FLAG_Update);//禁止ARR预装载缓冲器TIM_ARRPreloadConfig(TIM2, DISABLE);//开启TIM2的中断TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE);
}void NVIC_cfg()
{NVIC_InitTypeDef NVIC_InitStructure;//选择中断分组1NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);//选择TIM2的中断通道NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQChannel;      //抢占式中断优先级设置为0NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;//响应式中断优先级设置为0NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;//使能中断NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_Init(&NVIC_InitStructure);
}void GPIO_cfg()
{GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;                 //选择引脚5GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //输出频率最大50MHzGPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //带上拉电阻输出GPIO_Init(GPIOB,&GPIO_InitStructure);}在stm32f10x_it.c中，我们找到函数TIM2_IRQHandler()，并向其中添加代码void TIM2_IRQHandler(void){u8 ReadValue;//检测是否发生溢出更新事件if(TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET){//清除TIM2的中断待处理位TIM_ClearITPendingBit(TIM2 , TIM_FLAG_Update);//将PB.5管脚输出数值写入ReadValueReadValue = GPIO_ReadOutputDataBit(GPIOB,GPIO_Pin_5);           if(ReadValue == 0){GPIO_SetBits(GPIOB,GPIO_Pin_5);}    else{GPIO_ResetBits(GPIOB,GPIO_Pin_5);      }}
}