Mega 2560 External interrup

Projects General Guidance
1

Hii ,

I have mega 2560 and I use external interrup 0 (pin 2) and it is triggered falling edge. But it works very very slow . For example , pin 2 is high when ever it fall low , interrup work after 5 secods pass... Code is at below . Thank any help....

int pin = 13;
volatile int state = LOW;

void setup()
{
  Serial.begin(115200);
  pinMode(2, INPUT);
  pinMode(pin, OUTPUT);
  attachInterrupt(0, fiber, FALLING);
}

void loop()
{
  
}

void fiber()
{
  state = !state;
  digitalWrite(pin, state);
  
}
2

What signal is driving the line?
Might want to use

pinMode(2, INPUT_PULLUP);

so the line is not floating if using a switch that connects the Pin to Gnd for instance.; the internal pullup will then ensure the pin promptly returns high when released.

3

Jeez - I just replied to this question over there a few minutes ago - with the correct answer I think.

Don't double post.