/*******************************************************************************
* Function Name  : SysTick_Config
* Description    : Configures SysTick
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
//SysTick設置
void SysTick_Config(void)
{
    /* Disable SysTick Counter */
    SysTick_CounterCmd(SysTick_Counter_Disable);
  
    /* Disable the SysTick Interrupt */
    SysTick_ITConfig(DISABLE);
  
    /* Configure HCLK clock as SysTick clock source */
    SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK_Div8);

    /* SysTick interrupt each 1000 Hz with HCLK equal to 72MHz */
    SysTick_SetReload(9000);        

    /* Enable the SysTick Interrupt */
    SysTick_ITConfig(ENABLE);

}


/*******************************************************************************
* Function Name  : Delay_Ms
* Description    : Inserts a delay time.
* Input          : nTime: specifies the delay time length, in milliseconds.
* Output         : None
* Return         : None
*******************************************************************************/
void Delay_Ms(u32 nTime)
{
    /* Enable the SysTick Counter */
    SysTick_CounterCmd(SysTick_Counter_Enable);
  
    TimingDelay = nTime;

    while(TimingDelay != 0);

    /* Disable SysTick Counter */
    SysTick_CounterCmd(SysTick_Counter_Disable);
    /* Clear SysTick Counter */
    SysTick_CounterCmd(SysTick_Counter_Clear);
}


/*******************************************************************************
* Function Name  : TimingDelayMs_Decrement
* Description    : Decrements the TimingDelay variable.
* Input          : None
* Output         : TimingDelay
* Return         : None
*******************************************************************************/
void TimingDelay_Decrement(void)
{
    if (TimingDelay != 0x00)
    { 
      TimingDelay--;
    }
}
/*******************************************************************************
* Function Name  : SysTickHandler
* Description    : interrupt.
* Input          : None
* Output         : TimingDelay
* Return         : None
*******************************************************************************/
void SysTickHandler(void)
{ 
    TimingDelay_Decrement();
    
    {
    	/****一些計數可在此實現，1ms實現一次中斷******/
    }
}


使用時通過調用Delay_Ms（nTime）函數來設置精確延時