求助：我的main函数中调用TIM_SetCompare1确定输出占空比。TIM3TIM4均已正常工作，但TIM1始终不能正常工作。以下是我TIM1的初始化代码，请各位大神看看有啥问题没有。谢谢！！



void TIM1_PWM_Init(u16 arr,u16 psc)
{  
        GPIO_InitTypeDef GPIO_InitStructure;
        TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
        TIM_OCInitTypeDef  TIM_OCInitStructure;
        TIM_BDTRInitTypeDef TIM_BDTRInitStructure;

        RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);        //使能定时器1时钟
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);  //使能GPIO外设
       
    //GPIOA.10、11
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10 | GPIO_Pin_11;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //推挽输出
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIO

       
   //初始化TIM1
        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 = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
        TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
        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

        //初始化TIM1 Channel2 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_OutputNState = TIM_OutputState_Disable;
        TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low; //输出极性:TIM输出比较极性高
        TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCPolarity_Low; //输出极性:TIM输出比较极性高
        TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
        TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
        TIM_OC1Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM1 OC1
        TIM_OC2Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM1 OC2
        TIM_OC3Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM1 OC3
        TIM_OC4Init(TIM1, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM1 OC4

        TIM_BDTRInitStructure.TIM_OSSRState=TIM_OSSRState_Disable;
        TIM_BDTRInitStructure.TIM_OSSIState=TIM_OSSRState_Disable;
        TIM_BDTRInitStructure.TIM_LOCKLevel=TIM_LOCKLevel_OFF;
        TIM_BDTRInitStructure.TIM_DeadTime=0x0;
        TIM_BDTRInitStructure.TIM_Break=TIM_Break_Disable;
        TIM_BDTRInitStructure.TIM_BreakPolarity=TIM_BreakPolarity_High;
        TIM_BDTRInitStructure.TIM_AutomaticOutput=TIM_AutomaticOutput_Enable;
        TIM_BDTRConfig(TIM1,&TIM_BDTRInitStructure);

       
        TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的预装载寄存器
        TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的预装载寄存器
        TIM_OC3PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的预装载寄存器
        TIM_OC4PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的预装载寄存器
        TIM_ARRPreloadConfig(TIM1, ENABLE);
        TIM_Cmd(TIM1, ENABLE);  //使能TIM1
        TIM_CtrlPWMOutputs(TIM1 , ENABLE);

}