PID controller Sample Time

Projects Programming
6

Ok, maybe I should explain what this is about:
I use the throttle flap to control the air supply of my charcoal grill. The flap is meant to open / close depending of the temperature deviation (and gradient of temperature changes, that's why I think the PID is the right tool). As the temperature will only change slowly when the flap position changes, I want this to happen only once a minute. The main part of the code is:

myPID.Compute();
Input = thermocouple.readCelsius();
if (Input < Setpoint-1){

  • myPID.SetControllerDirection(DIRECT);*
  • pos=pos+Output;*
  • pos=min(pos,180);*
  • myservo.write(pos);*
  • Serial.print(pos);*
    }
    else if (Input > Setpoint +1) {
    myPID.SetControllerDirection(REVERSE);
  • pos= pos-Output;*
  • pos=max(pos,90);*
    myservo.write(pos);
    Serial.print(pos);
    }

How would I implement interrupt to this?

Axel