stm32的TIM1定时器能不能产生4MHZ的信号啊？我的定时器开起来，最多能达到2MHZ左右，再改预分频值和自动重装载寄存器周期值的也不会改变频率。。。。[mw_shl_code=applescript,true]void TIM1_Int_Init(u16 arr,u16 psc)
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;  
  NVIC_InitTypeDef NVIC_InitStructure;  
  
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE); //时钟使能

  //设置优先级  
  NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_TIM10_IRQn;   
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;//先占优先级0级  
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;       //从优先级0级  
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;  
  NVIC_Init(&NVIC_InitStructure);         
  
  TIM_TimeBaseStructure.TIM_Period = arr; //设置自动重装载寄存器周期值  
  TIM_TimeBaseStructure.TIM_Prescaler =(psc-1);//设置预分频值  
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割  
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//向上计数模式  
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;//重复计数设置  
        TIM_TimeBaseInit(TIM1,&TIM_TimeBaseStructure);
  TIM_ClearFlag(TIM1, TIM_FLAG_Update);//清中断标志位  
  
  TIM_ITConfig(TIM1,TIM_IT_Update,ENABLE);   
  
  TIM_Cmd(TIM1, ENABLE);  //使能TIMx外设  
}

//定时器3中断服务函数
void TIM1_UP_TIM10_IRQHandler(void)
{
                TIM_ClearITPendingBit(TIM1,TIM_IT_Update);  //清除中断标志位
                LED1=!LED1;//DS1翻转
}[/mw_shl_code]