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ManualsBrandsAdafruit ManualsAdafruitCircuit Playground Express

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def volume_color(volume):

return 200, volume * (255 // NUM_PIXELS), 0

# Main program

# Set up NeoPixels and turn them all off.

pixels = neopixel.NeoPixel(board.NEOPIXEL, NUM_PIXELS,

brightness=0.1, auto_write=False)

pixels.fill(0)

pixels.show()

# For CircuitPython 2.x:

mic = audiobusio.PDMIn(board.MICROPHONE_CLOCK, board.MICROPHONE_DATA,

frequency=16000, bit_depth=16)

# For Circuitpython 3.0 and up, "frequency" is now called "sample_rate".

# Comment the lines above and uncomment the lines below.

#mic = audiobusio.PDMIn(board.MICROPHONE_CLOCK, board.MICROPHONE_DATA,

# sample_rate=16000, bit_depth=16)

# Record an initial sample to calibrate. Assume it's quiet when we start.

samples = array.array('H', [0] * NUM_SAMPLES)

mic.record(samples, len(samples))

# Set lowest level to expect, plus a little.

input_floor = normalized_rms(samples) + 10

# OR: used a fixed floor

# input_floor = 50

# You might want to print the input_floor to help adjust other values.

# print(input_floor)

# Corresponds to sensitivity: lower means more pixels light up with lower sound

# Adjust this as you see fit.

input_ceiling = input_floor + 500

peak = 0

while True:

mic.record(samples, len(samples))

magnitude = normalized_rms(samples)

# You might want to print this to see the values.

# print(magnitude)

# Compute scaled logarithmic reading in the range 0 to NUM_PIXELS

c = log_scale(constrain(magnitude, input_floor, input_ceiling),

input_floor, input_ceiling, 0, NUM_PIXELS)

# Light up pixels that are below the scaled and interpolated magnitude.

pixels.fill(0)

for i in range(NUM_PIXELS):

if i < c:

pixels[i] = volume_color(i)

# Light up the peak pixel and animate it slowly dropping.

if c >= peak:

peak = min(c, NUM_PIXELS - 1)

elif peak > 0:

peak = peak - 1

if peak > 0:

pixels[int(peak)] = PEAK_COLOR

pixels.show()