//Example - Exernal interrupt

#define LED 13
void setup() {
  
  Serial.begin(9600);
  pinMode(LED, OUTPUT); // setup output
  attachInterrupt(digitalPinToInterrupt(2),displaymillis,RISING); 
  attachInterrupt(digitalPinToInterrupt(3),displaymicro,RISING); 

}

//ISR - external interupt
void displaymillis(){
  Serial.write("millis = ");
  Serial.println(millis());
}
void displaymicro(){
  Serial.write("micros = ");
  Serial.println(micros());
}

void loop() {
  
  digitalWrite(LED, HIGH);
  delay(500);
  digitalWrite(LED, LOW);
  delay(500);

}