import array, time
from machine import Pin
import rp2
# PIO state machine for RGB. Pulls 24 bits (rgb -> 3 * 8bit) automatically
@rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT, autopull=True, pull_thresh=24)
def ws2812():
T1 = 2
T2 = 5
T3 = 3
wrap_target()
label("bitloop")
out(x, 1) .side(0) [T3 - 1]
jmp(not_x, "do_zero") .side(1) [T1 - 1]
jmp("bitloop") .side(1) [T2 - 1]
label("do_zero")
nop().side(0) [T2 - 1]
wrap()
# PIO state machine for RGBW. Pulls 32 bits (rgbw -> 4 * 8bit) automatically
@rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT, autopull=True, pull_thresh=32)
def sk6812():
T1 = 2
T2 = 5
T3 = 3
wrap_target()
label("bitloop")
out(x, 1) .side(0) [T3 - 1]
jmp(not_x, "do_zero") .side(1) [T1 - 1]
jmp("bitloop") .side(1) [T2 - 1]
label("do_zero")
nop() .side(0) [T2 - 1]
wrap()
# Delay here is the reset time. You need a pause to reset the LED strip back to the initial LED
# however, if you have quite a bit of processing to do before the next time you update the strip
# you could put in delay=0 (or a lower delay)
#
# Class supports different order of individual colors (GRB, RGB, WRGB, GWRB ...). In order to achieve
# this, we need to flip the indexes: in 'RGBW', 'R' is on index 0, but we need to shift it left by 3 * 8bits,
# so in it's inverse, 'WBGR', it has exactly right index. Since micropython doesn't have [::-1] and recursive rev()
# isn't too efficient we simply do that by XORing (operator ^) each index with 3 (0b11) to make this flip.
# When dealing with just 'RGB' (3 letter string), this means same but reduced by 1 after XOR!.
# Example: in 'GRBW' we want final form of 0bGGRRBBWW, meaning G with index 0 needs to be shifted 3 * 8bit ->
# 'G' on index 0: 0b00 ^ 0b11 -> 0b11 (3), just as we wanted.
# Same hold for every other index (and - 1 at the end for 3 letter strings).
class Neopixel:
def __init__(self, num_leds, state_machine, pin, mode="RGB", delay=0.0001):
self.pixels = array.array("I", [0 for _ in range(num_leds)])
self.mode = set(mode) # set for better performance
if 'W' in self.mode:
# RGBW uses different PIO state machine configuration
self.sm = rp2.StateMachine(state_machine, sk6812, freq=8000000, sideset_base=Pin(pin))
# dictionary of values required to shift bit into position (check class desc.)
self.shift = {'R': (mode.index('R') ^ 3) * 8, 'G': (mode.index('G') ^ 3) * 8,
'B': (mode.index('B') ^ 3) * 8, 'W': (mode.index('W') ^ 3) * 8}
else:
self.sm = rp2.StateMachine(state_machine, ws2812, freq=8000000, sideset_base=Pin(pin))
self.shift = {'R': ((mode.index('R') ^ 3) - 1) * 8, 'G': ((mode.index('G') ^ 3) - 1) * 8,
'B': ((mode.index('B') ^ 3) - 1) * 8, 'W': 0}
self.sm.active(1)
self.num_leds = num_leds
self.delay = delay
self.brightnessvalue = 255
# Set the overal value to adjust brightness when updating leds
def brightness(self, brightness=None):
if brightness == None:
return self.brightnessvalue
else:
if brightness < 1:
brightness = 1
if brightness > 255:
brightness = 255
self.brightnessvalue = brightness
# Create a gradient with two RGB colors between "pixel1" and "pixel2" (inclusive)
# Function accepts two (r, g, b) / (r, g, b, w) tuples
def set_pixel_line_gradient(self, pixel1, pixel2, left_rgb_w, right_rgb_w):
if pixel2 - pixel1 == 0:
return
right_pixel = max(pixel1, pixel2)
left_pixel = min(pixel1, pixel2)
for i in range(right_pixel - left_pixel + 1):
fraction = i / (right_pixel - left_pixel)
red = round((right_rgb_w[0] - left_rgb_w[0]) * fraction + left_rgb_w[0])
green = round((right_rgb_w[1] - left_rgb_w[1]) * fraction + left_rgb_w[1])
blue = round((right_rgb_w[2] - left_rgb_w[2]) * fraction + left_rgb_w[2])
# if it's (r, g, b, w)
if len(left_rgb_w) == 4 and 'W' in self.mode:
white = round((right_rgb_w[3] - left_rgb_w[3]) * fraction + left_rgb_w[3])
self.set_pixel(left_pixel + i, (red, green, blue, white))
else:
self.set_pixel(left_pixel + i, (red, green, blue))
# Set an array of pixels starting from "pixel1" to "pixel2" (inclusive) to the desired color.
# Function accepts (r, g, b) / (r, g, b, w) tuple
def set_pixel_line(self, pixel1, pixel2, rgb_w):
for i in range(pixel1, pixel2 + 1):
self.set_pixel(i, rgb_w)
# Set red, green and blue value of pixel on position <pixel_num>
# Function accepts (r, g, b) / (r, g, b, w) tuple
def set_pixel(self, pixel_num, rgb_w):
pos = self.shift
red = round(rgb_w[0] * (self.brightness() / 255))
green = round(rgb_w[1] * (self.brightness() / 255))
blue = round(rgb_w[2] * (self.brightness() / 255))
white = 0
# if it's (r, g, b, w)
if len(rgb_w) == 4 and 'W' in self.mode:
white = round(rgb_w[3] * (self.brightness() / 255))
self.pixels[pixel_num] = white << pos['W'] | blue << pos['B'] | red << pos['R'] | green << pos['G']
# Converts HSV color to rgb tuple and returns it
# Function accepts integer values for <hue>, <saturation> and <value>
# The logic is almost the same as in Adafruit NeoPixel library:
# https://github.com/adafruit/Adafruit_NeoPixel so all the credits for that
# go directly to them (license: https://github.com/adafruit/Adafruit_NeoPixel/blob/master/COPYING)
def colorHSV(self, hue, sat, val):
if hue >= 65536:
hue %= 65536
hue = (hue * 1530 + 32768) // 65536
if hue < 510:
b = 0
if hue < 255:
r = 255
g = hue
else:
r = 510 - hue
g = 255
elif hue < 1020:
r = 0
if hue < 765:
g = 255
b = hue - 510
else:
g = 1020 - hue
b = 255
elif hue < 1530:
g = 0
if hue < 1275:
r = hue - 1020
b = 255
else:
r = 255
b = 1530 - hue
else:
r = 255
g = 0
b = 0
v1 = 1 + val
s1 = 1 + sat
s2 = 255 - sat
r = ((((r * s1) >> 8) + s2) * v1) >> 8
g = ((((g * s1) >> 8) + s2) * v1) >> 8
b = ((((b * s1) >> 8) + s2) * v1) >> 8
return r, g, b
# Rotate <num_of_pixels> pixels to the left
def rotate_left(self, num_of_pixels):
if num_of_pixels == None:
num_of_pixels = 1
self.pixels = self.pixels[num_of_pixels:] + self.pixels[:num_of_pixels]
# Rotate <num_of_pixels> pixels to the right
def rotate_right(self, num_of_pixels):
if num_of_pixels == None:
num_of_pixels = 1
num_of_pixels = -1 * num_of_pixels
self.pixels = self.pixels[num_of_pixels:] + self.pixels[:num_of_pixels]
# Update pixels
def show(self):
# If mode is RGB, we cut 8 bits of, otherwise we keep all 32
cut = 8
if 'W' in self.mode:
cut = 0
for i in range(self.num_leds):
self.sm.put(self.pixels[i], cut)
time.sleep(self.delay)
# Set all pixels to given rgb values
# Function accepts (r, g, b) / (r, g, b, w)
def fill(self, rgb_w):
for i in range(self.num_leds):
self.set_pixel(i, rgb_w)
time.sleep(self.delay)