from machine import Pin
import time

# Define the onboard LED (GPIO 25)
led = Pin(25, Pin.OUT)

while True:
    led.value(1)  # Turn LED on
    time.sleep(0.5)  # Wait for 0.5 seconds
    led.value(0)  # Turn LED off
    time.sleep(0.5)  # Wait for 0.5 seconds