void TIM1_Init( void )
{
    // 16分频         16M/(0x0f+1)=1M   CNTR计数一次为 1/1M=1us 定时1000us
    TIM1_TimeBaseInit( 0x0f, TIM1_COUNTERMODE_UP, 1000, 0 );
    TIM1_ClearFlag( TIM1_FLAG_UPDATE );
    TIM1_ITConfig( TIM1_IT_UPDATE, ENABLE );  // 使能更新中断
    enableInterrupts();                       // 使能全局中断
}

INTERRUPT_HANDLER( TIM1_UPD_OVF_TRG_BRK_IRQHandler, 11 )
{
    /* In order to detect unexpected events during development,
       it is recommended to set a breakpoint on the following instruction.
    */
    TIM1_ClearITPendingBit( TIM1_IT_UPDATE );
    time1_num--;
    if( 0 == time1_num )
    {
        TIM1_Cmd( DISABLE );
        time1_Flag = 1;
    }
}