External interrupt 0/1

External interrupt 0 or 1 is essentially the same, only EX and IT are changed to 0 or 1.

Q: So the question is: Why do we have two very similar external interrupts 0 or 1?

A: When there are two external interrupts, if there is only one external interrupt,

Then when one interrupt handles two external interrupts, its CPU processing is not accurate enough.

Therefore, we need to open another channel to handle external interrupts.

Q: What if there are three external interrupts?

A: This is the limitation of the microcontroller. Haha~~ But the flight control has many interrupts

#include

/*

* External interrupt 0

*/

sbit LED = P2^0; //bit declaration

//Register initialization function

void kinson()

{

EX0 = 1; // External interrupt 0 switch

EA = 1; //Interrupt the main switch

IT0 = 1; //External interrupt 0 trigger mode: 0 is level, 1 is falling edge //The timer is to be started

}

//Main function

void main(void)

{

kinson(); //Calling the register initialization function

while(1); //Let the program loop infinitely here

}

//Interrupt

void xjx() interrupt 0 //The interrupt number of external interrupt 0 is 0, and the interrupt number of external interrupt 1 is 2

{

LED = ~LED; //The LED turns on and off because of each interrupt

}

#include

/*

* External interrupt 1

*/

sbit LED = P2^0; //bit declaration

//Register initialization function

void kinson()

{

EX1 = 1; // External interrupt 0 switch

EA = 1; //Interrupt the main switch

IT1 = 1; //External interrupt 0 trigger mode: 0 is level, 1 is falling edge //The timer is to be started

}

//Main function

void main(void)

{

kinson(); //Calling the register initialization function

while(1); //Let the program loop infinitely here

}

//Interrupt

void xjx() interrupt 2 //The interrupt number of external interrupt 0 is 0, and the interrupt number of external interrupt 1 is 2

{

LED = ~LED; //The LED turns on and off because of each interrupt

}