在stm32f1xx_ll_utils.c中提供的延时函数,以下标红语句为什么要多加1呢?延时1ms不就变成2ms了吗?
void LL_mDelay(uint32_t Delay)
{
__IO uint32_t tmp = SysTick->CTRL; /* Clear the COUNTFLAG first */
/* Add this code to indicate that local variable is not used */
((void)tmp);
/* Add a period to guaranty minimum wait */
if (Delay < LL_MAX_DELAY)
{
Delay++;
}
while (Delay)
{
if ((SysTick->CTRL & SysTick_CTRL_COUNTFLAG_Msk) != 0U)
{
Delay--;
}
}
}
|