void setup() {
  // put your setup code here, to run once:
  // comment or remark
  // this program was written by Wat Sir
  Serial.begin(115200);
  Serial.println("Hello, Kelvin Wat");
  pinMode(2, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  // delay(10); // this speeds up the simulation
  // Serial.println("Hello, Kelvin Wat 12345");
  digitalWrite(2, HIGH);
  delay(500);
  digitalWrite(2, LOW);
  delay(1500);
}