文章目录

• main.c
• timer.c
• timer.h

main.c

#include "led.h"
#include "delay.h"
#include "sys.h"
#include "timer.h"
#include "usart.h"

extern u8  TIM2CH1_CAPTURE_STA;		//输入捕获状态		    				
extern u16	TIM2CH1_CAPTURE_VAL;	//输入捕获值
 int main(void)
 {	
	 
	u32 temp=0; 
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);// 设置中断优先级分组2
	delay_init();	    	 //延时函数初始化	
	uart_init(9600);	 			//9600	 
	LED_Init();		  	//初始化与LED连接的硬件接口
 	TIM1_PWM_Init(899,0); 			//不分频。PWM频率=72000/(899+1)=80Khz
 	TIM2_Cap_Init(0XFFFF,72-1);		//以1Mhz的频率计数 
   	while(1)
	{
 		delay_ms(10);
		TIM_SetCompare1(TIM1,TIM_GetCapture1(TIM1)+1);
		if(TIM_GetCapture1(TIM1)==300)TIM_SetCompare1(TIM1,0);		 
		if(TIM2CH1_CAPTURE_STA&0X80)//成功捕获到了一次高电平
		{
			temp=TIM2CH1_CAPTURE_STA&0X3F;
			temp*=65536;					//溢出时间总和
			temp+=TIM2CH1_CAPTURE_VAL;		//得到总的高电平时间
			printf("HIGH:%d us\r\n",temp);	//打印总的高点平时间
 			TIM2CH1_CAPTURE_STA=0;			//开启下一次捕获
 		}
	}
}

timer.c

#include "timer.h"
#include "led.h"
#include "usart.h"
#include "sys.h"

//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
void TIM1_PWM_Init(u16 arr,u16 psc)
{  
	 GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;

	RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);// 
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);  //使能GPIO外设时钟使能
	                                                                     	

   //设置该引脚为复用输出功能,输出TIM1 CH2的PWM脉冲波形
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8; //TIM_CH2
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //复用推挽输出
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	
	TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值	 80K
	TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值  不分频
	TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
	TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

 
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //选择定时器模式:TIM脉冲宽度调制模式2
	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
	TIM_OCInitStructure.TIM_Pulse = 0; //设置待装入捕获比较寄存器的脉冲值
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
	TIM_OC1Init(TIM1, &TIM_OCInitStructure);  //根据TIM_OCInitStruct中指定的参数初始化外设TIMx

  TIM_CtrlPWMOutputs(TIM1,ENABLE);	//MOE 主输出使能	

	TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);  //CH1预装载使能	 
	
	TIM_ARRPreloadConfig(TIM1, ENABLE); //使能TIMx在ARR上的预装载寄存器
	
	TIM_Cmd(TIM1, ENABLE);  //使能TIM1
 
   
}

//定时器2通道1输入捕获配置

TIM_ICInitTypeDef  TIM2_ICInitStructure;

void TIM2_Cap_Init(u16 arr,u16 psc)
{	 
	GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
 	NVIC_InitTypeDef NVIC_InitStructure;

	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);	//使能TIM2时钟
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);  //使能GPIOA时钟
	
	GPIO_InitStructure.GPIO_Pin  = GPIO_Pin_0;  //PA0 清除之前设置  
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入  
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	GPIO_ResetBits(GPIOA,GPIO_Pin_0);						 //PA0 下拉
	
	//初始化定时器2 TIM2	 
	TIM_TimeBaseStructure.TIM_Period = arr; //设定计数器自动重装值 
	TIM_TimeBaseStructure.TIM_Prescaler =psc; 	//预分频器   
	TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
  
	//初始化TIM2输入捕获参数
	TIM2_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01 	选择输入端 IC1映射到TI1上
  	TIM2_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;	//上升沿捕获
  	TIM2_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上
  	TIM2_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;	 //配置输入分频,不分频 
  	TIM2_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
  	TIM_ICInit(TIM2, &TIM2_ICInitStructure);
	
	//中断分组初始化
	NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;  //TIM2中断
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;  //先占优先级2级
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;  //从优先级0级
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
	NVIC_Init(&NVIC_InitStructure);  //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器 
	
	TIM_ITConfig(TIM2,TIM_IT_Update|TIM_IT_CC1,ENABLE);//允许更新中断 ,允许CC1IE捕获中断	
	
  TIM_Cmd(TIM2,ENABLE ); 	//使能定时器2
 
}


u8  TIM2CH1_CAPTURE_STA=0;	//输入捕获状态		    				
u16	TIM2CH1_CAPTURE_VAL;	//输入捕获值
 
//定时器5中断服务程序	 
void TIM2_IRQHandler(void)
{ 

 	if((TIM2CH1_CAPTURE_STA&0X80)==0)//还未成功捕获	
	{	  
		if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
		 
		{	    
			if(TIM2CH1_CAPTURE_STA&0X40)//已经捕获到高电平了
			{
				if((TIM2CH1_CAPTURE_STA&0X3F)==0X3F)//高电平太长了
				{
					TIM2CH1_CAPTURE_STA|=0X80;//标记成功捕获了一次
					TIM2CH1_CAPTURE_VAL=0XFFFF;
				}else TIM2CH1_CAPTURE_STA++;
			}	 
		}
	if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)//捕获1发生捕获事件
		{	
			if(TIM2CH1_CAPTURE_STA&0X40)		//捕获到一个下降沿 		
			{	  			
				TIM2CH1_CAPTURE_STA|=0X80;		//标记成功捕获到一次上升沿
				TIM2CH1_CAPTURE_VAL=TIM_GetCapture1(TIM2);
		   		TIM_OC1PolarityConfig(TIM2,TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获
			}else  								//还未开始,第一次捕获上升沿
			{
				TIM2CH1_CAPTURE_STA=0;			//清空
				TIM2CH1_CAPTURE_VAL=0;
	 			TIM_SetCounter(TIM2,0);
				TIM2CH1_CAPTURE_STA|=0X40;		//标记捕获到了上升沿
		   		TIM_OC1PolarityConfig(TIM2,TIM_ICPolarity_Falling);		//CC1P=1 设置为下降沿捕获
			}		    
		}			     	    					   
 	}
 
    TIM_ClearITPendingBit(TIM2, TIM_IT_CC1|TIM_IT_Update); //清除中断标志位
 
}

timer.h

#ifndef __TIMER_H
#define __TIMER_H
#include "sys.h"

 
 
void TIM1_PWM_Init(u16 arr,u16 psc);
void TIM2_Cap_Init(u16 arr,u16 psc);

#endif