适用环境

驱动库：基于正点原子的底层驱动库
适用范围：STM32F103Cxxx,STM32F103Rxxx,STM32F103Zxxx（其他型号的没有测试）

配置代码

//TIM3 PWM部分初始化 
//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
void TIM3_PWM_Init(u32 arr,u32 psc)
{		 					 
	//此部分需手动修改IO口设置
	
	GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;
	
   //当没有重映射时，TIM3的四个通道CH1，CH2，CH3，CH4分别对应PA6，PA7,PB0,PB1
   //当部分重映射时，TIM3的四个通道CH1，CH2，CH3，CH4分别对应PB4，PB5,PB0,PB1
   //当完全重映射时，TIM3的四个通道CH1，CH2，CH3，CH4分别对应PC6，PC7,PC8,PC9
   
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);  	//TIM3时钟使能    
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE); 	//使能PORTF时钟	
	GPIO_PinRemapConfig(GPIO_FullRemap_TIM3, ENABLE);       //完全重映映射
    
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_8|GPIO_Pin_9;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;	//速度100MHz
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;      //推挽复用输出
	GPIO_Init(GPIOC,&GPIO_InitStructure);             //初始化PF9
	  
    //时间计算：周期T = ((1+TIM_Prescaler )/72M)*(1+TIM_Period) (单位S)
    TIM_InternalClockConfig(TIM3);  //采用内部时钟给TIM3提供时钟源
    
	TIM_TimeBaseStructure.TIM_Prescaler=psc;  //定时器分频   //
	TIM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
	TIM_TimeBaseStructure.TIM_Period=arr;   //自动重装载值  
	TIM_TimeBaseStructure.TIM_ClockDivision=TIM_CKD_DIV1; 	
	TIM_TimeBaseInit(TIM3,&TIM_TimeBaseStructure);//初始化定时器4
    
    
	//初始化TIM3 PWM模式	   
    
	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_OCPolarity = TIM_OCPolarity_High;     //输出极性:TIM输出比较极性高
    
    //TIM3_CH1
    TIM_OCInitStructure.TIM_Pulse = 0;  //设置待装入捕获比较寄存器的脉冲值
    TIM_OC1Init(TIM3, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM4OC1
    TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能TIM4在CCR1上的预装载寄存器
    
    //TIM3_CH2
    TIM_OCInitStructure.TIM_Pulse = 0;  //设置待装入捕获比较寄存器的脉冲值
    TIM_OC2Init(TIM3, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM4OC2
    TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能TIM4在CCR2上的预装载寄存器
    
    //TIM3_CH3
    TIM_OCInitStructure.TIM_Pulse = 0;  //设置待装入捕获比较寄存器的脉冲值
    TIM_OC3Init(TIM3, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM4OC3
    TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能TIM4在CCR3上的预装载寄存器
    
    //TIM3_CH4
    TIM_OCInitStructure.TIM_Pulse = 0;  //设置待装入捕获比较寄存器的脉冲值
    TIM_OC4Init(TIM3, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM4OC4
    TIM_OC4PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能TIM4在CCR4上的预装载寄存器

    TIM_Cmd(TIM3, ENABLE); 
    
    //初始化后默认PWM输出为0,
    TIM_SetCompare1(TIM3,0);        //占空比 = 0 / TIM_Period * 100%  
    TIM_SetCompare2(TIM3,0);
    TIM_SetCompare1(TIM3,0);
    TIM_SetCompare2(TIM3,0);								  
}