/*
  Forum: https://forum.arduino.cc/t/led-blinking-irregularly-is-my-device-damaged/1217047
  Wokwi: https://wokwi.com/projects/388191341984986113
*/

int counter = 0;

void setup() {
  Serial.begin(9600);

 pinMode(10,OUTPUT);
 pinMode(13,OUTPUT);
}

void loop() {
   digitalWrite(10, HIGH);
   digitalWrite(13, HIGH);
   delay(500);
   digitalWrite(10, LOW);
   digitalWrite(13, LOW);
   
   delay(5000);

   Serial.println(counter++);
}