import machine, neopixel, time
from machine import ADC
leds = 25
np = neopixel.NeoPixel(machine.Pin(2), leds) # Pin 4 as data pin
adc = ADC(machine.Pin(34)) # Analog read from Pin 22

def read_sound_level():
    return adc.read() # Reads analog value from 0-4095 on ESP32

def map_sound_to_color(sound_level):
    intensity = min(255, int(sound_level / 16)) # Map the 12-bit value to an 8-bit value
    return (intensity, 0, 0) # Only use red color

def fade_pixel(np, index):
    r, _, _ = np[index]
    np[index] = (int(r*0.9), 0, 0) # Only fade red component

while True:
    sound_level = read_sound_level()
    new_color = map_sound_to_color(sound_level)
    
    # Shift and fade colors
    for i in range(leds - 1, 0, -1):
        np[i] = np[i-1]
    np[0] = new_color

    for i in range(1, leds):
        fade_pixel(np, i)

    np.write()
    time.sleep_ms(33) # Control speed to aim for ~30 FPS


main.py

diagram.json

from machine import Pin
from neopixel import NeoPixel
from time import sleep

RED = (127, 0, 0)
OFF = (0, 0, 0)
NUM_BARS = 4
PIXELS_PER_BAR = 8
TOTAL_PIXELS = NUM_BARS * PIXELS_PER_BAR

pixels = NeoPixel(Pin(15), TOTAL_PIXELS)

def set_bar_pixel(bar, pixel, color):
    if bar % 2 == 0:  # For even bars, pixels run top-down
        index = bar * PIXELS_PER_BAR + pixel
    else:  # For odd bars, pixels run bottom-up
        index = (bar + 1) * PIXELS_PER_BAR - pixel - 1
    pixels[index] = color

while True:
    for i in range(PIXELS_PER_BAR):  # For each pixel in a bar
        for bar in range(NUM_BARS):  # For each bar
            set_bar_pixel(bar, i, RED)
        pixels.write()
        sleep(0.1)

        # Turn off the pixels for the next round
        for bar in range(NUM_BARS):
            set_bar_pixel(bar, i, OFF)
        pixels.write()


MoveDown.py

from machine import Pin
from neopixel import NeoPixel
from time import sleep

RED = (127, 0, 0)
OFF = (0, 0, 0)
NUM_BARS = 4
PIXELS_PER_BAR = 8
TOTAL_PIXELS = NUM_BARS * PIXELS_PER_BAR

pixels = NeoPixel(Pin(15), TOTAL_PIXELS)

def set_bar_pixel(bar, pixel, color):
    if bar % 2 == 0:  # For even bars, pixels run top-down
        index = bar * PIXELS_PER_BAR + pixel
    else:  # For odd bars, pixels run bottom-up
        index = (bar + 1) * PIXELS_PER_BAR - pixel - 1
    pixels[index] = color

while True:
    # First and Third bars move down, Second and Fourth bars move up
    for i in range(PIXELS_PER_BAR):
        # Turn on the pixel at the i-th position for each bar
        set_bar_pixel(0, i, RED)  # 1st bar, move down
        set_bar_pixel(1, PIXELS_PER_BAR - i - 1, RED)  # 2nd bar, move up
        set_bar_pixel(2, i, RED)  # 3rd bar, move down
        set_bar_pixel(3, PIXELS_PER_BAR - i - 1, RED)  # 4th bar, move up

        pixels.write()
        sleep(0.1)

        # Turn off the pixels for the next round
        set_bar_pixel(0, i, OFF)
        set_bar_pixel(1, PIXELS_PER_BAR - i - 1, OFF)
        set_bar_pixel(2, i, OFF)
        set_bar_pixel(3, PIXELS_PER_BAR - i - 1, OFF)
        pixels.write()


UpandDown.py

# NeoPixels Rainbow on MicroPython
# Wokwi Example https://wokwi.com/arduino/projects/305569065545499202

from machine import Pin
from neopixel import NeoPixel
from time import sleep

RED = (127,0,0)
pixels = NeoPixel(Pin(15), 32)
while True:
  
  for i in range(32):
    pixels[i] = RED
    pixels.write()
    sleep(0.1)
    pixels[i] = (0,0,0)
    pixels.write()



Basic.py

from machine import Pin
from neopixel import NeoPixel
from time import sleep

RED = (127, 0, 0)
GREEN = (0, 127, 0)
OFF = (0, 0, 0)
NUM_BARS = 4
PIXELS_PER_BAR = 8
TOTAL_PIXELS = NUM_BARS * PIXELS_PER_BAR

pixels = NeoPixel(Pin(15), TOTAL_PIXELS)

def set_bar_pixel(bar, pixel, color):
    if bar % 2 == 0:  # For even bars, pixels run top-down
        index = bar * PIXELS_PER_BAR + pixel
    else:  # For odd bars, pixels run bottom-up
        index = (bar + 1) * PIXELS_PER_BAR - pixel - 1
    pixels[index] = color

def set_bar_pixel_reverse(bar, pixel, color):
    if bar % 2 == 0:  # For even bars, pixels run top-down
        index = (bar + 1) * PIXELS_PER_BAR - pixel - 1
    else:  # For odd bars, pixels run bottom-up
        
        index = bar * PIXELS_PER_BAR + pixel
    pixels[index] = color

while True:
    # First and Third bars move down, Second and Fourth bars move up
    for i in range(1,PIXELS_PER_BAR):
        # Turn on the pixel at the i-th position for each bar
        set_bar_pixel(0, i, RED)  # 1st bar, move down
        set_bar_pixel(1, PIXELS_PER_BAR - i - 1, RED)  # 2nd bar, move up
        set_bar_pixel(2, i, RED)  # 3rd bar, move down
        set_bar_pixel(3, PIXELS_PER_BAR - i - 1, RED)  # 4th bar, move up

        pixels.write()
        sleep(0.1)

        # Turn off the pixels for the next round
        set_bar_pixel(0, i, OFF)
        set_bar_pixel(1, PIXELS_PER_BAR - i - 1, OFF)
        set_bar_pixel(2, i, OFF)
        set_bar_pixel(3, PIXELS_PER_BAR - i - 1, OFF)
        pixels.write()

    for i in range(1,PIXELS_PER_BAR):
        # Turn on the pixel at the i-th position for each bar
        set_bar_pixel_reverse(0, i, RED)  # 1st bar, move down
        set_bar_pixel_reverse(1, PIXELS_PER_BAR - i - 1, RED)  # 2nd bar, move up
        set_bar_pixel_reverse(2, i, RED)  # 3rd bar, move down
        set_bar_pixel_reverse(3, PIXELS_PER_BAR - i - 1, RED)  # 4th bar, move up

        pixels.write()
        sleep(0.1)

        # Turn off the pixels for the next round
        set_bar_pixel_reverse(0, i, OFF)
        set_bar_pixel_reverse(1, PIXELS_PER_BAR - i - 1, OFF)
        set_bar_pixel_reverse(2, i, OFF)
        set_bar_pixel_reverse(3, PIXELS_PER_BAR - i - 1, OFF)
        pixels.write()

    
