from machine import Pin
import time
time.sleep(0.1) # Wait for USB to become ready

print("Hello, Pi Pico!")


# Define pin numbers
RED = 1
GREEN = 9

# Set up pins as outputs
red_pin = Pin(RED, Pin.OUT)
green_pin = Pin(GREEN, Pin.OUT)

def traffic_light_cycle():
    # Green light
    green_pin.on()
    time.sleep(3)

    # Green to Red transition
    green_pin.off()
    time.sleep(0.5)

    # Red light
    red_pin.on()
    time.sleep(2)

    # Red to Green transition
    time.sleep(0.5)
    red_pin.off()

# Main loop
while True:
    traffic_light_cycle()