我的tim1定时器中断debug的时候跳到startup_stm32f40_41xxx中去了，而且还跳不出来了。怎么办？
以下是我的代码：
        TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
        NVIC_InitTypeDef NVIC_InitStructure;
       
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1,ENABLE);
        NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
       
        NVIC_InitStructure.NVIC_IRQChannel=TIM1_UP_TIM10_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x00;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x00;
        NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
        NVIC_Init(&NVIC_InitStructure);
       
       TIM_TimeBaseInitStructure.TIM_Period = 10000-1;        
        TIM_TimeBaseInitStructure.TIM_Prescaler= 8400-1;
        TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up;
        TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1;
        TIM_TimeBaseInitStructure.TIM_RepetitionCounter=0;
       
        TIM_TimeBaseInit(TIM1,&TIM_TimeBaseInitStructure);
       
        TIM_ITConfig(TIM1,TIM_IT_Update,ENABLE);
        TIM_Cmd(TIM1,ENABLE);