stm32 PWM实现呼吸灯

#include "stm32f10x.h"


void PWM_Init(void)
{
	//PB0默认TIM3_CH3通道
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
	
	//配置PB0为复用推挽输出
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;		//复用推挽输出，中断控制来自片上外设（TIM3_CH3），而非输出数据寄存器
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	//设置TIM3定时器内部时钟源
	TIM_InternalClockConfig(TIM3);
	//频率为1kHz, 占空比为50%，分辨率为1%
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
	TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
	TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
	TIM_TimeBaseInitStructure.TIM_Period = 100 - 1;		//ARR
	TIM_TimeBaseInitStructure.TIM_Prescaler = 720 - 1;		//PSC
	TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
	TIM_TimeBaseInit(TIM3, &TIM_TimeBaseInitStructure);
	//清除更新标志位
	TIM_ClearFlag(TIM3, TIM_FLAG_Update);
	TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);	//TIM3中断配置使能
	
	TIM_OCInitTypeDef	TIM_OCInitStructure;
	TIM_OCStructInit(&TIM_OCInitStructure);		//给结构体赋初始值
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;		//输出比较模式
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;	//极性选择
	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;	//输出使能
	TIM_OCInitStructure.TIM_Pulse = 0;		//CCR
	TIM_OC3Init(TIM3, &TIM_OCInitStructure);
	//打开TIM3定时器外设
	TIM_Cmd(TIM3, ENABLE);
	
}


//PWM占空比的函数
void PWM_SetCompare3(uint16_t Compare3)
{
	TIM_SetCompare3(TIM3, Compare3);
}

#ifndef __PWM_H
#define __PWM_H
void PWM_Init(void);
void PWM_SetCompare3(uint16_t Compare3);

#endif

#include "stm32f10x.h"
#include "Delay.h"
#include "OLED.h"
#include "PWM.h"

uint8_t i;

int main(void)
{
	PWM_Init();		//PWM初始化
	
	while(1)	
	{	
		for(i = 0; i <= 100; i ++)
		{
			PWM_SetCompare3(i);		//设置TIM3捕获比较3寄存器的值，即CRR
			Delay_ms(10);
		}
		for(i = 0; i <= 100; i ++)
		{
			PWM_SetCompare3(100 - i);
			Delay_ms(10);
		}
		
	}
}