a very simple Cheerlights/NeoPixel MQTT client for MicroPython

mqtt_cheerlights.py

# -*- coding: utf-8 -*-
# scruss, 2024-12
# MicroPython
"""
 a very simple Cheerlights MQTT client for MicroPython
 Uses Peter Hinch's MicroPython Asynchronous MQTT library
  — https://github.com/peterhinch/micropython-mqtt/

 Install it with:
  mpremote mip install github:peterhinch/micropython-mqtt

 Edit local and neopixel configuration sections below
"""
from mqtt_as import MQTTClient, config
import asyncio
import machine
from neopixel import NeoPixel
# from apa106 import APA106  # if you are using (G, R, B) LEDs

# Local configuration
config["ssid"] = "Your_wifi_SSID"
config["wifi_pw"] = "Your_wifi_password"
MQTTClient.DEBUG = False  # print diagnostic messages if true

# begin board specific neopixel configuration
"""
 My board - Wemos S3 MINI PRO - has one addressable LED
 on Pin 8, but unusually has a Enable/Power signal on Pin 7
 Check your board details.
 Some boards make RGB LEDs too bright and wash out the colours,
 so maybe set 'bri' to an integer between 2-4
"""
_ = machine.Pin(7, machine.Pin.OUT, value=1)  # neopixel power
neopin = Pin(8, Pin.OUT)  # control pin
np = NeoPixel(neopin, 1)  # we have one whole LED here
bri = 1  # LED brightness divisor (integer)
# end board specific neopixel setup

# *** no need to edit anything below here ***

np.fill(
    (24 // bri, 48 // bri, 96 // bri)
)  # light pixels to show they work
np.write()
config["server"] = "mqtt.cheerlights.com"


def callback(topic, msg, retained, properties=None):
    print("Colour:", msg.decode())
    m = msg.decode()  # is a hex RGB string like '#ff00ff'
    np.fill(
        (
            int(m[1:3], 16) // bri,
            int(m[3:5], 16) // bri,
            int(m[5:7], 16) // bri,
        )
    )
    np.write()


async def conn_han(client):
    await client.subscribe("hex", 0)


async def main(client):
    await client.connect()
    while True:
        # hang around forever waiting for messages to come in
        await asyncio.sleep(5)


config["subs_cb"] = callback
config["connect_coro"] = conn_han
client = MQTTClient(config)
try:
    asyncio.run(main(client))
finally:
    client.close()  # Prevent LmacRxBlk:1 errors

np.fill((0, 0, 0))
np.write()  # turn off neopixels for tidiness