from machine import Pin
from neopixel import NeoPixel
from time import sleep_ms

pin = Pin(13, Pin.OUT)
np = NeoPixel(pin, 16)

while True:
    for x in range(16):
        np[x] = (0, 0, 255)
        np.write()
        sleep_ms(1000)
    
    for x in range(16):
        np[x] = (0, 0, 0)
        np.write()
        sleep_ms(1000)