Here's an example project you can do with your Nunchuck breakout to control some NeoPixels with joystick, button, and motion from a Wii Nunchuck.
Parts
You can use pretty much any CircuitPython-capable board for this, I had a Metro M4 Airlift handy.
This will work with any NeoPixel strand, strip, or ring.
Wiring
Use the STEMMA QT/qwiic to male header pin adapter to plug the Nunchuck breakout into your microcontroller's 3.3V, GND, SDA, & SCL lines.
Wire your NeoPixels into the board's 5V, GND, and D6 (to NeoPixel DIN) pins (if your board only has 3.3V that's usually fine, too, but NeoPixels prefer 5V when available).
Then, plug your Nunchuck controller into the adapter, making sure to follow the silkscreened "NOTCH UP" guidline.
Code
Set up your board as shown on the previous page, then download this code onto the board as code.py.
# SPDX-FileCopyrightText: 2021 John Park for Adafruit Industries
#
# SPDX-License-Identifier: MIT
import time
import board
import adafruit_nunchuk
import neopixel
import simpleio
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
nc = adafruit_nunchuk.Nunchuk(i2c)
# create neopixel object
NEOPIN = board.D6
NEOLENGTH = 60
NEOORDER = neopixel.GRBW # set to GRB for 'regular' RGB NeoPixels
pixels = neopixel.NeoPixel(
NEOPIN, NEOLENGTH, brightness=0.1, auto_write=False, pixel_order=NEOORDER
)
RED = (220, 0, 0)
PURPLE = (80, 0, 160)
PINK = (100, 0, 80)
GREEN = (0, 180, 0)
CYAN = (0, 80, 100)
BLUE = (0, 0, 255)
BLACK = (0, 0, 0)
COLORS = [RED, PURPLE, PINK, GREEN, CYAN, BLUE]
pix = 0 # selected pixel
color_pick = 0 # current color index
pixels.fill(BLACK)
pixels.show()
while True:
x, y = nc.joystick # get joystick values
ax, ay, az = nc.acceleration # get accelerometer values
tilt_x = simpleio.map_range(ax, 300.0, 800.0, 0.0, 1.0) # remap tilt to brightness
# remap y to current pixel
pix = int(
simpleio.map_range(y, 0, 255, 0, NEOLENGTH - 1)
)
if nc.button_C: # hold C button to use tilt for brightness
pixels.brightness = tilt_x
if nc.button_Z:
color_pick = (color_pick + 1) % 4 # cycle through colors
time.sleep(0.02) # debounce
pixels.fill(BLACK) # turn off pixels
for i in range(0, pix + 1): # light up all pixels up to the current one
pixels[i] = COLORS[color_pick]
pixels.show()
Now, you can control your LEDs with the nunchuck!
- move the joystick up and down to choose how many pixels are lit
- tap the Z button to change colors
- hold the C button while tilting the controller from side to side to adjust brightness. Let go of the C button to lock in that brightness level
