【stm32-5】输入捕获模式测频率&PWMI模式测频率占空比

1.输入捕获模式测频率

（1）main.c

#include "Device/Include/stm32f10x.h"   // Device header
#include "pwm.h"
#include "delay.h"
#include "OLED.h"
#include "IC.h"
uint8_t i;
int main(void)
{
//PWM模块将待测信号输出到PA0，PA0通过导线，输入到PA6（TIM3的通道1）：通过输入捕获模块，测量得到频率
	OLED_Init();
	PWM_Init();
	IC_Init();
	OLED_ShowString(1,1,"Freq:00000HZ");
	
	PWM_SetPrescaler(720-1);		//Freq=72M/(PSC+1)/(ARR+1)
	PWM_setcompare1(50);			//Duty=CCR/100
	while(1)
	{
		OLED_ShowNum(1,6,IC_GetFreq(),5);
	}
}

(2) pwm.c

#include "Device/Include/stm32f10x.h"   // Device header
void PWM_Init(void)
{
//根据PWM基本结构框图，时基单元初始化、输出比较单元选择(TIM1通道初始化)
	
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);	//打开时钟
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;	//复用推挽输出（输出控制权转移给片上外设）
	GPIO_InitStructure.GPIO_Pin=GPIO_Pin_0;
	GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStructure);
	
	TIM_InternalClockConfig(TIM2);	//选择内部时钟
	
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitstructure;	//初始化时基单元
	TIM_TimeBaseInitstructure.TIM_ClockDivision=TIM_CKD_DIV1;
	TIM_TimeBaseInitstructure.TIM_CounterMode=TIM_CounterMode_Up;
	TIM_TimeBaseInitstructure.TIM_Period=100-1;
	//定时器周期，实际就是ARR的值。CCR的值直接就是占空比（分辨率为1%）,若ARR为1000，分辨率为0.1%
	TIM_TimeBaseInitstructure.TIM_Prescaler=720-1;//通过改变PSC来改变PWM频率
	TIM_TimeBaseInitstructure.TIM_RepetitionCounter=0;//重复计数器，高级控制寄存器专用寄存器位，这里不用设置
	TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitstructure);//初始化定时器
	
	TIM_OCInitTypeDef TIM_OCInitstructure;
	TIM_OCStructInit(&TIM_OCInitstructure);	//结构体赋初始值
	TIM_OCInitstructure.TIM_OCMode=TIM_OCMode_PWM1;
	TIM_OCInitstructure.TIM_OCPolarity=TIM_OCPolarity_High;
	TIM_OCInitstructure.TIM_OutputState=TIM_OutputState_Enable;	//输出状态
	TIM_OCInitstructure.TIM_Pulse=0;	//CCR的值
	TIM_OC1Init(TIM2,&TIM_OCInitstructure);	//使用PA0口，对应第一个通道，使用OC1Init函数
	//TIM1通道初始化
	TIM_Cmd(TIM2,ENABLE);//计数器使能，启动定时器
}
void PWM_setcompare1(uint16_t compare)
{
	TIM_SetCompare1(TIM2,compare);//CCR的值
}
void PWM_SetPrescaler(uint16_t Prescaler)
{
	TIM_PrescalerConfig(TIM2,Prescaler,TIM_PSCReloadMode_Immediate);//写入PSC//立刻生效
}

(3) IC.c

#include "Device/Include/stm32f10x.h"   // Device header
void IC_Init(void)
{
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);	//打开时钟选择PA6.TIM3_CH1
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IPU;	
	//上拉输入，定时器TIM2345引脚，输入捕获通道GPIO应使用浮空输入
	GPIO_InitStructure.GPIO_Pin=GPIO_Pin_6;
	GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStructure);
	
	TIM_InternalClockConfig(TIM3);	//选择内部时钟
	
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitstructure;	//初始化时基单元
	TIM_TimeBaseInitstructure.TIM_ClockDivision=TIM_CKD_DIV1;
	TIM_TimeBaseInitstructure.TIM_CounterMode=TIM_CounterMode_Up;
	TIM_TimeBaseInitstructure.TIM_Period=65536-1;//防止计数溢出
	//定时器周期，实际就是ARR的值。CCR的值直接就是占空比（分辨率为1%）,若ARR为1000，分辨率为0.1%
	TIM_TimeBaseInitstructure.TIM_Prescaler=72-1;//通过改变PSC来改变PWM频率
	TIM_TimeBaseInitstructure.TIM_RepetitionCounter=0;//重复计数器，高级控制寄存器专用寄存器位，这里不用设置
	TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitstructure);//初始化定时器
	
	TIM_ICInitTypeDef TIM_ICInitstructure;
	TIM_ICInitstructure.TIM_Channel=TIM_Channel_1;//
	TIM_ICInitstructure.TIM_ICFilter=0xf;//选择输入比较滤波器，在0x0-0xf之间
	TIM_ICInitstructure.TIM_ICPolarity=TIM_ICPolarity_Rising;
	TIM_ICInitstructure.TIM_ICPrescaler=TIM_ICPSC_DIV1;//??????????
	TIM_ICInitstructure.TIM_ICSelection=TIM_ICSelection_DirectTI;//不分频
	TIM_ICInit(TIM3,&TIM_ICInitstructure);//初始化
	
	TIM_SelectInputTrigger(TIM3,TIM_TS_TI1FP1);//触发源选择
	TIM_SelectSlaveMode(TIM3,TIM_SlaveMode_Reset);//选择从模式
	
	TIM_Cmd(TIM3,ENABLE);//开启定时器
	
}
uint32_t IC_GetFreq(void)
{
	return 1000000/TIM_GetCapture1(TIM3);//fx=fc/N(HZ);
	
}

2.PWMI模式测频率占空比

(1)main.c

#include "Device/Include/stm32f10x.h"   // Device header
#include "pwm.h"
#include "delay.h"
#include "OLED.h"
#include "IC.h"
uint8_t i;
int main(void)
{
//PWM模块将待测信号输出到PA0，PA0通过导线，输入到PA6（TIM3的通道1）：通过输入捕获模块，测量得到频率
	OLED_Init();
	PWM_Init();
	IC_Init();
	OLED_ShowString(1,1,"Freq:00000HZ");
	OLED_ShowString(2,1,"Duty:00%");
	PWM_SetPrescaler(720-1);		//Freq=72M/(PSC+1)/(ARR+1)
	PWM_setcompare1(50);			//Duty=CCR/100
	while(1)
	{
		OLED_ShowNum(1,6,IC_GetFreq(),5);
		OLED_ShowNum(2,6,IC_GetDuty(),2);
	}
}

(2)IC.c

#include "Device/Include/stm32f10x.h"   // Device header
void IC_Init(void)
{
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);	//打开时钟选择PA6.TIM3_CH1
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IPU;	//上拉输入
	GPIO_InitStructure.GPIO_Pin=GPIO_Pin_6;
	GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
	GPIO_Init(GPIOA,&GPIO_InitStructure);
	
	TIM_InternalClockConfig(TIM3);	//选择内部时钟
	
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitstructure;	//初始化时基单元
	TIM_TimeBaseInitstructure.TIM_ClockDivision=TIM_CKD_DIV1;
	TIM_TimeBaseInitstructure.TIM_CounterMode=TIM_CounterMode_Up;
	TIM_TimeBaseInitstructure.TIM_Period=65536-1;//防止计数溢出
	//定时器周期，实际就是ARR的值。CCR的值直接就是占空比（分辨率为1%）,若ARR为1000，分辨率为0.1%
	TIM_TimeBaseInitstructure.TIM_Prescaler=72-1;//通过改变PSC来改变PWM频率
	TIM_TimeBaseInitstructure.TIM_RepetitionCounter=0;//重复计数器，高级控制寄存器专用寄存器位，这里不用设置
	TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitstructure);//初始化定时器
	
	TIM_ICInitTypeDef TIM_ICInitstructure;
	TIM_ICInitstructure.TIM_Channel=TIM_Channel_1;
	TIM_ICInitstructure.TIM_ICFilter=0x0;
	TIM_ICInitstructure.TIM_ICPolarity=TIM_ICPolarity_Rising;
	TIM_ICInitstructure.TIM_ICPrescaler=TIM_ICPSC_DIV1;
	TIM_ICInitstructure.TIM_ICSelection=TIM_ICSelection_DirectTI;
	//TIM_ICInit(TIM3,&TIM_ICInitstructure);
	TIM_PWMIConfig(TIM3,&TIM_ICInitstructure);//PWMI基本结构
	
	TIM_SelectInputTrigger(TIM3,TIM_TS_TI1FP1);//触发源选择
	TIM_SelectSlaveMode(TIM3,TIM_SlaveMode_Reset);//选择从模式
	
	TIM_Cmd(TIM3,ENABLE);
	
}
uint32_t IC_GetFreq(void)
{
	return 1000000/(TIM_GetCapture1(TIM3)+1);//fx=fc/N(HZ);
	
}
uint32_t IC_GetDuty(void)
{
	return (TIM_GetCapture2(TIM3)+1)*100/(TIM_GetCapture1(TIM3)+1);
}