INTERRUPT – ARM

int a=0; void setup() {   pinMode(PF_2, OUTPUT); //for blue led   pinMode(PF_3, OUTPUT); //for green led   pinMode(PUSH2, INPUT_PULLUP);   attachInterrupt(PF_0, blinky, FALLING); // Interrupt is fired whenever button is pressed                                          //  Here Blinky is interrupt service function } void loop()  //normally this loop plays  {   digitalWrite(PF_2, 1); //blue LED starts ON   delay(1000);   digitalWrite(PF_2, 0); //blue LED starts Off   delay(1000); } void blinky() //this loop will excute when interrupt occur {   a = !a;  digitalWrite(PF_3,a);  // output of green led will negate }