from machine import Pin
from time import sleep_ms

clk = Pin(18, Pin.OUT, value=0)

cycle = 0
while True:
    clk.value(0)
    sleep_ms(1500)
    print(f"Cycle: {cycle} LOW")

    clk.value(1)
    sleep_ms(1500)
    print(f"Cycle: {cycle} HIGH")

    cycle += 1