rainbow_cycle.py

# SPDX-FileCopyrightText: 2017 Mike Causer <https://github.com/mcauser>
# SPDX-License-Identifier: MIT

"""
MicroPython P9813 RGB LED driver
https://github.com/mcauser/micropython-p9813
"""

from machine import Pin
from time import sleep_ms
import p9813

# TinyPICO (esp32)
clk = Pin(4, Pin.OUT)
data = Pin(14, Pin.OUT)

# Bit-banged, 10 LEDs, auto-write off
num_leds = 10
chain = p9813.P9813_BITBANG(clk, data, num_leds, False)


def rainbow_cycle(repeats, sleep):
    # n cycles of all colors on wheel
    for _ in range(repeats):
        for n in range(256):
            for i in range(num_leds):
                chain[i] = wheel(((i * 256 // num_leds) + n) & 255)
            chain.write()
        sleep_ms(sleep)


# Helper for converting 0-255 offset to a colour tuple
def wheel(offset):
    # The colours are a transition r - g - b - back to r
    offset = 255 - offset
    if offset < 85:
        return (255 - offset * 3, 0, offset * 3)
    if offset < 170:
        offset -= 85
        return (0, offset * 3, 255 - offset * 3)
    offset -= 170
    return (offset * 3, 255 - offset * 3, 0)


# Fade all LEDs together through rainbow colours, offset each LED
rainbow_cycle(5, 10)