It's easy to use the IoT Button with NeoPixel BFF with CircuitPython and the Adafruit_CircuitPython_NeoPixel module. This module allows you to easily write Python code that lets you control NeoPixels. A second example will use the Adafruit_CircuitPython_AdafruitIO module to let you write Python code to communicate with Adafruit IO, Adafruit's IoT platform.
CircuitPython Microcontroller Wiring
Plug an IoT Button with NeoPixel BFF into your QT Py or Xiao form factor board exactly as shown below. Here's an example of connecting a QT Py ESP32-S2 to the BFF.
Connect the QT Py ESP32-S2 with pin headers into the IoT Button with NeoPixel BFF with socket headers. They should be plugged in with the backs of the boards facing each other.
For more information on soldering socket headers, check out this Learn Guide.
CircuitPython Usage
To use with CircuitPython, you need to first install the NeoPixel library, and its dependencies, into the lib folder on your CIRCUITPY drive. Then you need to update code.py with the example script.
Thankfully, we can do this in one go. In the example below, click the Download Project Bundle button below to download the necessary libraries and the code.py file in a zip file. Extract the contents of the zip file, and copy the entire lib folder and the code.py file to your CIRCUITPY drive.
Your CIRCUITPY/lib folder should contain the following folders and files:
- /adafruit_io
- /adafruit_minimqtt
- adafruit_pixelbuf.mpy
- adafruit_requests.mpy
- neopixel.mpy
# SPDX-FileCopyrightText: 2023 Liz Clark for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""Basic IoT Button with NeoPixel BFF Example"""
import time
import board
from digitalio import DigitalInOut, Direction, Pull
from rainbowio import colorwheel
import neopixel
# setup onboard NeoPixel
pixel_pin = board.A3
num_pixels = 1
pixels = neopixel.NeoPixel(pixel_pin, num_pixels, brightness=0.3, auto_write=False)
# setup onboard button
switch = DigitalInOut(board.A2)
switch.direction = Direction.INPUT
switch.pull = Pull.UP
# rainbow cycle function
def rainbow_cycle(wait):
for j in range(255):
for i in range(num_pixels):
rc_index = (i * 256 // num_pixels) + j
pixels[i] = colorwheel(rc_index & 255)
pixels.show()
time.sleep(wait)
while True:
# run rainbow cycle animation
rainbow_cycle(0)
# if the button is not pressed..
if switch.value:
# neopixel brightness is zero and appears to be "off"
pixels.brightness = 0
# if the button is pressed..
else:
# neopixel brightness is 0.3 and rainbow animation is visible
pixels.brightness = 0.3
Once everything is saved to the CIRCUITPY drive, you can press and hold the button on the BFF to make the rainbow animation show on the NeoPixel. If you release the button, the NeoPixel will stop showing the animation.
Adafruit IO Example
To run this example for Adafruit IO, be sure to first review the Welcome to Adafruit IO Learn Guide and read how to setup your settings.toml file to store your WiFi and Adafruit IO credentials on your CIRCUITPY drive.
# SPDX-FileCopyrightText: 2023 Liz Clark for Adafruit Industries
# SPDX-License-Identifier: MIT
"""Simple Adafruit IO Example for IoT Button with NeoPixel BFF"""
import os
import time
import ssl
import wifi
import socketpool
import microcontroller
import board
from digitalio import DigitalInOut, Direction, Pull
import neopixel
import adafruit_requests
from adafruit_io.adafruit_io import IO_HTTP, AdafruitIO_RequestError
# setup onboard button
switch = DigitalInOut(board.A2)
switch.direction = Direction.INPUT
switch.pull = Pull.UP
# setup onboard NeoPixel
pixel_pin = board.A3
num_pixels = 1
pixels = neopixel.NeoPixel(pixel_pin, num_pixels, brightness=0.3, auto_write=False)
# neopixel status colors
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
# red until connecting
pixels.fill(RED)
pixels.show()
wifi.radio.connect(os.getenv('CIRCUITPY_WIFI_SSID'), os.getenv('CIRCUITPY_WIFI_PASSWORD'))
aio_username = os.getenv('aio_username')
aio_key = os.getenv('aio_key')
pool = socketpool.SocketPool(wifi.radio)
requests = adafruit_requests.Session(pool, ssl.create_default_context())
# Initialize an Adafruit IO HTTP API object
io = IO_HTTP(aio_username, aio_key, requests)
print("connected to io")
# blue when talking to IO
pixels.fill(BLUE)
pixels.show()
try:
# get feed
button_feed = io.get_feed("buttonbff")
except AdafruitIO_RequestError:
# if no feed exists, create one
button_feed = io.create_new_feed("buttonbff")
# green once connected
pixels.fill(GREEN)
pixels.show()
# button press count sent to IO
count = 0
while True:
try:
# if the button is pressed..
if not switch.value:
# blue when talking to IO
pixels.fill(BLUE)
pixels.show()
# increase by 1 with press
count += 1
# send count to feed
io.send_data(button_feed["key"], count)
print("sent %d" % count)
print()
# delay
time.sleep(5)
else:
# green if connected
pixels.fill(GREEN)
pixels.show()
# pylint: disable=broad-except
# any errors, reset board
except Exception as e:
# neopixels red with an error
pixels.fill(RED)
pixels.show()
print("Error:\n", str(e))
print("Resetting microcontroller in 10 seconds")
time.sleep(10)
microcontroller.reset()
In the code, the value of the variable count is sent to Adafruit IO every time you press the button. The value increases by 1 with each button press. You can see this data in your Adafruit IO feed.
The NeoPixel acts as an Adafruit IO status light. If your board is connected, the NeoPixel is green. If your board is actively uploading data to Adafruit IO, the NeoPixel is blue. If there is an error or connection problem, the NeoPixel is red.
