2-2.STM32之定时器TIM---输入捕获--实验2（ PWMI模式测频率占空比）

输入捕获模式测频率、PWMI模式测频率占空比-****博客  参考这篇文章！

来利用一个GPIO的定时器的两个通道进行捕获占空比和频率，看出可以看出。TI1FP1和TI2FP2，计数值分别在CCR1和CCR2中取，

测周法

IC.c

#include "stm32f10x.h"                  // Device header

void IC_Init(void)
{
	//开启时钟
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
	
	
	//配置GPIO
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;		//GPIO_Pin_15;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	
	
	
	
	//开启时基单元
	TIM_InternalClockConfig(TIM3);
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
	TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
	TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
	TIM_TimeBaseInitStructure.TIM_Period = 65536 - 1;		//ARR
	TIM_TimeBaseInitStructure.TIM_Prescaler = 72 - 1;		//PSC
	TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
	TIM_TimeBaseInit(TIM3, &TIM_TimeBaseInitStructure);
	
	
	
	//初始化输入捕获单元
	TIM_ICInitTypeDef TIM_ICInitStructure;
	TIM_ICInitStructure.TIM_Channel = TIM_Channel_1; //选择通道一
	TIM_ICInitStructure.TIM_ICFilter = 0xF; //选择滤波器
	TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
	TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //不分频
	TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //直连通道
	TIM_ICInit(TIM3,&TIM_ICInitStructure);
	
	//方式1  配置PWMI模式  自动选择通道2和下降沿触发、间接通道，与上相反
	TIM_PWMIConfig(TIM3,&TIM_ICInitStructure);
	
	
//方式2	
//	TIM_ICInitStructure.TIM_Channel = TIM_Channel_2; //选择通道一
//	TIM_ICInitStructure.TIM_ICFilter = 0xF; //选择滤波器
//	TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling; //下降沿触发
//	TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //不分频
//	TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_IndirectTI; //间接通道
//	TIM_ICInit(TIM3,&TIM_ICInitStructure);
	
	
	//主从模式配置
	TIM_SelectInputTrigger(TIM3,TIM_TS_TI1FP1);  //触发源选择
	TIM_SelectSlaveMode(TIM3,TIM_SlaveMode_Reset); //从模式配置
	
	TIM_Cmd(TIM3,ENABLE); //启动定时器
}



uint16_t IC_GetFreq(void)  //获取最新一个周期的频率值
{
	return 1000000/ (TIM_GetCapture1(TIM3)+1); 
}


uint16_t IC_GetDuty(void)  //测占空比
{
	return (TIM_GetCapture2(TIM3)+1) *100 / (TIM_GetCapture1(TIM3)+1) ;
}

main.c

#include "stm32f10x.h"                  // Device header
#include "Delay.h"
#include "OLED.h"
#include "PWM.h"
#include "IC.h"

uint8_t i;

int main(void)
{
	OLED_Init();
	PWM_Init();
	IC_Init();
	
	OLED_ShowString(1,1,"Freq:00000Hz");
	OLED_ShowString(2,1,"Duty:000%");
	
	PWM_SetPrescaler(7200-1);   //Freq = 72M / (PSC+1) / (ARR+1)
	PWM_SetCompare1(50);   //Duty = CCR/ARR+1
	while (1)
	{
		OLED_ShowNum(1,6,IC_GetFreq(),5);
		OLED_ShowNum(2,6,IC_GetDuty(),3);
	}
}