void setup() {
  // Set PB3 (Pin 2) as an output
  pinMode(3, OUTPUT); // PB3 corresponds to digital pin 3 on ATtiny85
}

void loop() {
  digitalWrite(3, HIGH); // Turn the LED on
  delay(500);            // Wait for 500ms
  digitalWrite(3, LOW);  // Turn the LED off
  delay(500);            // Wait for 500ms
}