STM32庫函數EXTI_GetFlagStatus和EXTI_GetIT

EXTI_GetFlagStatus只是純粹讀取中斷標志位的狀態(tài)，但是不一定會(huì )響應中斷（EXT_IMR寄存器對該中斷進(jìn)行屏蔽）；而EXTI_GetITStatus除了讀取中斷標志位，還查看EXT_IMR寄存器是否對該中斷進(jìn)行屏蔽，在中斷掛起&沒(méi)有屏蔽的情況下就會(huì )響應中斷。仔細看看代碼就知道區別了
FlagStatus EXTI_GetFlagStatus(uint32_t EXTI_Line)
{
FlagStatus bitstatus = RESET;

assert_param(IS_GET_EXTI_LINE(EXTI_Line));

if ((EXTI->PR & EXTI_Line) != (uint32_t)RESET)
{
bitstatus = SET;
}
else
{
bitstatus = RESET;
}
return bitstatus;
}

ITStatus EXTI_GetITStatus(uint32_t EXTI_Line)
{
ITStatus bitstatus = RESET;
uint32_t enablestatus = 0;

assert_param(IS_GET_EXTI_LINE(EXTI_Line));

enablestatus = EXTI->IMR & EXTI_Line;
if (((EXTI->PR & EXTI_Line) != (uint32_t)RESET) && (enablestatus != (uint32_t)RESET))
{
bitstatus = SET;
}
else
{
bitstatus = RESET;
}
return bitstatus;
}