void setup() {
  pinMode(PB4, OUTPUT); // Setup the pins
  pinMode(PB3, INPUT);

}

void loop() {
  int inputVal - analogRead(PB3); // Read the input pin
  if(inputVal > 1000){ // If enough electricity enters
    blinkLED(5); // Blink the LED 5 times    
  }
}

void blinkLED(int numBlink){
  int num = 0;
  delay(1000);
  while(num < numBlink){
    digitalWrite(PB4, HIGH);
    delay(500);
    digitalWrite(PB4, HIGH);
    delay(500);
    num += 1;
  }
}