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Raspbery Pi Pico Bluetooth LED

Control LEDs over Bluetooth.

Wiring

The Code

main.py

import json
import neopixel
from led import Led
from machine import UART, Pin
 
uart = UART(0, 9600)
led = Led()
 
while True:
    if uart.any():
        received = uart.read()
        try:
            input = received.decode("utf-8")
            payload = json.loads(input)
            command: str = payload["command"] 
        except:
            # Return command in case of decoding error
            # so the script does not break
            command: str = "error"
 
        if command == "on":
            R,G,B,brightness = payload["data"]["r"] , payload["data"]["g"], payload["data"]["b"], payload["data"]["brightness"]
            led.on(int(R), int(G), int(B), int(brightness))
            status: str = led.status()
            uart.write(status.encode("utf-8"))
 
        elif command == "off":
            led.off()
            status: str = led.status()
            uart.write(status.encode("utf-8"))
 
        elif command == "status":
            status = led.status()
            encoded = status.encode("UTF-8")
            uart.write(encoded)
        elif command == "error":
            print(received)

led.py

import time
from machine import Pin
import neopixel
import json
 
class Led:
    pin = Pin(13) # Pico GPIO13 (number 17)
    count = 39 # Number of LEDs on the strip
    state = {"command": "state", "state": 0, "r": 0, "g": 0, "b": 0, "brightness": 0}
    initialState = state
    strip = neopixel.NeoPixel(pin, count)
 
    def on(self, R: int, G: int, B: int, brightness: int = 100):
        strip = self.strip
 
        for i in range(self.count):
            strip[i] = (round(R * brightness / 100), round(G * brightness / 100), round(B * brightness / 100))
            strip.write()
            time.sleep(0.02)
        self.state = {"command": "state", "state": 1, "r": R, "g": G, "b": B, "brightness": brightness}
 
    def off(self):
        strip = self.strip
 
        for i in range(39):
            strip[i] = (0, 0, 0)
        strip.write()
        strip = self.initialState
 
    def status(self):
        return json.dumps(self.state)

Download the neopixel.py module.