proteus仿真stm32f103c8定时器定时1秒遇到的问题

void Timer_Init(void)
{
    /*1.开启时钟*/
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    
    /*2.选择时基单元时钟*/
    TIM_InternalClockConfig(TIM2);
    
    /*3.配置时基单元*/
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInitStructure.TIM_Period = 10000 - 1;  //ARR, 计时频率=晶振频率/(PSC+1)/(ARR+1)
    TIM_TimeBaseInitStructure.TIM_Prescaler = 400 - 1;  //PSC,预分频器和计数器都有1个数的偏差，所以减一
    TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
    
    /*4.使能更新中断*/
    TIM_ClearFlag(TIM2, TIM_FLAG_Update); //解决复位就进入中断+1的状态
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_Init(&NVIC_InitStructure);

    /*启动定时器*/
    TIM_Cmd(TIM2, ENABLE);
}

理论上内部72MHz的时钟应该是分频给个7200 - 1 ，，

还没搞懂proteus的stm32是怎么搞的，预分频用的400-1才能实现1S定时， ，估计是程序哪里没有配置倍频？留个棋子后面研究。。

void Timer_Init(void){/*1.开启时钟*/RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);/*2.选择时基单元时钟*/TIM_InternalClockConfig(TIM2);/*3.配置时基单元*/TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;TIM_TimeBaseInitStructure.TIM_Period = 10000 - 1;  //ARR, 计时频率=晶振频率/(PSC+1)/(ARR+1)TIM_TimeBaseInitStructure.TIM_Prescaler = 400 - 1;  //PSC,预分频器和计数器都有1个数的偏差，所以减一TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);/*4.使能更新中断*/TIM_ClearFlag(TIM2, TIM_FLAG_Update); //解决复位就进入中断+1的状态TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);NVIC_InitTypeDef NVIC_InitStructure;NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;NVIC_Init(&NVIC_InitStructure);
/*启动定时器*/TIM_Cmd(TIM2, ENABLE);}