stm32f103 TIM1发PWM

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);//定时器1时钟使能
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);//GPIOB时钟使能

        //GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
        GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_14 | GPIO_Pin_15;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;//复用推挽输出
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

        GPIO_Init(GPIOB, &GPIO_InitStructure);
 
        //初始化TIM3
        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
        TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值
        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
#if 1        //TIM1CHN通道发出PWM    
    //初始化TIM3 Channel2 PWM模式    
        TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Disable;    //TIM_CH,这个注意选择，不然CHN通道发不出PWM !
        TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;    //TIM_CHN
        TIM_OCInitStructure.TIM_Pulse = 0;
        TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
        TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_Low;//决定波形高低电平
        TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;        //跟死区有关，还没研究
        TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;         

#else        //TM1CH通道输出PWM

   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_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
#endif 
    TIM_OC2Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM3 OC2
    TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM3在CCR2上的预装载寄存器

    TIM_OC3Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM3 OC2
    TIM_OC3PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM3在CCR2上的预装载寄存器
 
   TIM_ARRPreloadConfig(TIM1, ENABLE); //使能TIMx在ARR上的预装载寄存器
           TIM_Cmd(TIM1, ENABLE);  //使能TIM3
  TIM_CtrlPWMOutputs(TIM1, ENABLE);    //高级定时器主意打开 
}