Adafruit CircuitPython NeoPixel All In One
Raspberry Pi
& Python &WS2812B
RGB LED Strip
neopixel
# install for current user
$ pip3 install adafruit-circuitpython-neopixel
# install system-wide
$ sudo pip3 install adafruit-circuitpython-neopixel
https://pypi.org/project/adafruit-circuitpython-neopixel/
https://github.com/adafruit/Adafruit_CircuitPython_NeoPixel
docs
https://readthedocs.org/projects/adafruit-circuitpython-neopixel/
https://docs.circuitpython.org/projects/neopixel/en/latest/
https://docs.circuitpython.org/projects/neopixel/en/latest/index.html
https://docs.circuitpython.org/projects/neopixel/en/3.1.1/_modules/neopixel.html
API
neopixel.GRB= 'GRB'
Green Red Blue
neopixel.GRBW= 'GRBW'
Green Red Blue White
Class:
neopixel.NeoPixel(pin: Pin, n: int, *, bpp: int = 3, brightness: float = 1.0, auto_write: bool = True, pixel_order: str = None)
A sequence of neopixels.
Parameters:
pin
(Pin) – The pin to output neopixel data on.
n
(int) – The number of neopixels in the chain
bpp
(int) – Bytes per pixel. 3
for RGB and 4
for RGBW pixels.
brightness
(float) – Brightness of the pixels between 0.0 and 1.0 where 1.0 is full brightness
auto_write
(bool) – True if the neopixels should immediately change when set. If False, show must be called explicitly.
pixel_orde
r (str) – Set the pixel color channel order. GRBW is set by default.
https://docs.circuitpython.org/projects/neopixel/en/latest/api.html
#!/usr/bin/env python3
# coding: utf8
import neopixel
import board
from time import sleep
# neopixel.NeoPixel(pin: Pin, n: int, *, bpp: int = 3, brightness: float = 1.0, auto_write: bool = True, pixel_order: str = None)
# pixels = neopixel.NeoPixel(board.D18, 60, brightness=0.2, auto_write: False, pixel_order: neopixel.GRB)
pixels = neopixel.NeoPixel(board.D18, 60, brightness=0.2, auto_write: True, pixel_order: neopixel.GRB)
#!/usr/bin/env python3
# coding: utf8
import neopixel
import board
from time import sleep
# neopixel.NeoPixel(pin: Pin, n: int, *, bpp: int = 3, brightness: float = 1.0, auto_write: bool = True, pixel_order: str = None)
pixels = neopixel.NeoPixelboard.NEOPIXEL, 60, brightness=0.2, auto_write: False, pixel_order: neopixel.GRB)
pixels = neopixel.NeoPixel(board.NEOPIXEL, 60, brightness=0.2, auto_write: True, pixel_order: neopixel.GRB)
Python 函数参数的传递方式 ???
匿名参数
具名参数
- 具名参数前面的参数可以省略参数名
- 具名参数后面的参数必须写参数名
#!/usr/bin/env python3
# coding: utf8
def func_args(arg1: int, arg2: str = None, arg3: float = 1.0, arg4: bool = True):
print("arg1 {}".format(arg1))
print("arg2 {}".format(arg2))
print("arg3 {}".format(arg3))
print("arg4 {}".format(arg4))
# 全部使用匿名参数 ✅
func_args(60, "LEDs", 0.2, False)
# 全部使用匿名参数 ✅
func_args(arg1: 60, arg2: "LEDs", arg3: 0.2, arg4: ,False)
# 混合使用,前面匿名参数,后面具名参数 ✅
func_args(60, "LEDs", arg3: 0.2, arg4: False)
# 混合使用,前面匿名参数,中间具名参数,后面匿名参数 ❌
func_args(60, "LEDs", arg3: 0.2, False)
Python online REPL
https://www.runoob.com/try/runcode.php?filename=HelloWorld&type=python3
bugs ❌
https://github.com/adafruit/Adafruit_CircuitPython_NeoPixel/issues/151
https://github.com/adafruit/Adafruit_CircuitPython_NeoPixel/issues/153
demos
Feather M0 Express
andMetro M0 Express
#!/usr/bin/env python3
# coding: utf8
import board
import neopixel
# 1 LEDs ❓
pixels = neopixel.NeoPixel(board.NEOPIXEL, 1)
pixels[0] = (10, 0, 0)
https://www.adafruit.com/product/3403
https://www.adafruit.com/product/3505
Circuit Playground Express
#!/usr/bin/env python3
# coding: utf8
import board
import neopixel
# 10 LEDs❓
pixels = neopixel.NeoPixel(board.NEOPIXEL, 10, auto_write=False)
pixels[0] = (10, 0, 0)
pixels[9] = (0, 10, 0)
pixels.show()
https://www.adafruit.com/product/3333
#!/usr/bin/env python3
# coding: utf8
import board
import neopixel
pixels = neopixel.NeoPixel(board.NEOPIXEL, 10, auto_write=False)
# RGB test
pixels[0] = (255, 0, 0)
pixels[1] = (0, 255, 0)
pixels[2] = (0, 0, 255)
pixels.show()