今天尝试用sysTick来构造10ms的延时函数Delay()，但是似乎严重不准确，我Delay(500)，应该得到5s的延时，但我掐着表，2秒钟就从串口发出数据了。奇怪。高手多多指教~~
systick的设置
void SysTick_Config(void)
{
/* Configure HCLK clock as SysTick clock source */
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK);//HLCK is 72MHz,so the source of sysTick is 72MHz.
SysTick_SetReload(720000);
// 每tick一次,过去 1/72M 秒; 达到720,000次,则过去0.01s(10ms).
/* Enable the SysTick Interrupt */
SysTick_ITConfig(ENABLE);
}
中断处理函数
void SysTickHandler(void)
{
if(TimingDelay != 0)
TimingDelay--;
}
delay函数
void Delay(u32 param)
{
/* Enable the SysTick Counter */
SysTick_CounterCmd(SysTick_Counter_Enable);
TimingDelay = param;
while(TimingDelay != 0)
{
}
SysTick_CounterCmd(SysTick_Counter_Disable);
SysTick_CounterCmd(SysTick_Counter_Clear);
}
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