树莓派控制WS2812屏幕（python）

与树莓派连接

红色------5V
白色------GND
绿色-----GPIO18（树莓派第12个引脚）

代码

GitHub：git clone https://github.com/jgarff/rpi_ws281x

首先需要安装相关库：最好用pip3安装，这样python3就可以运行程序

sudo pip3 install rpi-ws281x

•  

若没有安装pip的还得先安装pip和pip3：（装了则跳过此步骤）

sudo apt-get install python-pip3

•  

要求-Limitations:

PWM

Since this library and the onboard Raspberry Pi audio both use the PWM, they cannot be used together. You will need to blacklist the Broadcom audio kernel module by creating a file sudo nano /etc/modprobe.d/snd-blacklist.conf with

编辑/etc/modprobe.d/snd-blacklist.conf文件，把下面的配置写进去

blacklist snd_bcm2835

If the audio device is still loading after blacklisting, you may also need to comment it out in the sudo nano /etc/modules file.

On headless systems you may also need to force audio through hdmi Edit config.txt and add:

编辑/etc/modules文件，把下面的配置写进去后重启树莓派

hdmi_force_hotplug=1
hdmi_force_edid_audio=1

A reboot is required for this change to take effect

Some distributions use audio by default, even if nothing is being played. If audio is needed, you can use a USB audio device instead.

 

以下为灯光多种变换的代码，一个函数一种变换：

import time
from rpi_ws281x import PixelStrip, Color
import argparse

LED_COUNT = 16        # LED灯的个数
LED_PIN = 18          # DI端接GPIO18

# 以下可以不用改
LED_FREQ_HZ = 800000  # LED signal frequency in hertz (usually 800khz)
LED_DMA = 10          # DMA channel to use for generating signal (try 10)
LED_BRIGHTNESS = 255  # Set to 0 for darkest and 255 for brightest
LED_INVERT = False    # True to invert the signal (when using NPN transistor level shift)
LED_CHANNEL = 0       # set to '1' for GPIOs 13, 19, 41, 45 or 53

# 以下为LED模式变换的各个函数
def colorWipe(strip, color, wait_ms=20):
    """一次擦除显示像素的颜色."""
    for i in range(strip.numPixels()):
        strip.setPixelColor(i, color)
        strip.show()
        time.sleep(wait_ms / 1000.0)

def theaterChase(strip, color, wait_ms=50, iterations=10):
    """电影影院灯光风格的追逐动画."""
    for j in range(iterations):
        for q in range(3):
            for i in range(0, strip.numPixels(), 3):
                strip.setPixelColor(i + q, color)
            strip.show()
            time.sleep(wait_ms / 1000.0)
            for i in range(0, strip.numPixels(), 3):
                strip.setPixelColor(i + q, 0)

def wheel(pos):
    """生成横跨0-255个位置的彩虹颜色."""
    if pos < 85:
        return Color(pos * 3, 255 - pos * 3, 0)
    elif pos < 170:
        pos -= 85
        return Color(255 - pos * 3, 0, pos * 3)
    else:
        pos -= 170
        return Color(0, pos * 3, 255 - pos * 3)

def rainbow(strip, wait_ms=20, iterations=1):
    """绘制彩虹，褪色的所有像素一次."""
    for j in range(256 * iterations):
        for i in range(strip.numPixels()):
            strip.setPixelColor(i, wheel((i + j) & 255))
        strip.show()
        time.sleep(wait_ms / 1000.0)

def rainbowCycle(strip, wait_ms=10, iterations=5):
    """画出均匀分布在所有像素上的彩虹."""
    for j in range(256 * iterations):
        for i in range(strip.numPixels()):
            strip.setPixelColor(i, wheel(
                (int(i * 256 / strip.numPixels()) + j) & 255))
        strip.show()
        time.sleep(wait_ms / 1000.0)

def theaterChaseRainbow(strip, wait_ms=50):
    """旋转的彩色灯光."""
    for j in range(256):
        for q in range(3):
            for i in range(0, strip.numPixels(), 3):
                strip.setPixelColor(i + q, wheel((i + j) % 255))
            strip.show()
            time.sleep(wait_ms / 1000.0)
            for i in range(0, strip.numPixels(), 3):
                strip.setPixelColor(i + q, 0)

# Main program logic follows:
if __name__ == '__main__':
    # Process arguments
    parser = argparse.ArgumentParser()
    parser.add_argument('-c', '--clear', action='store_true', help='clear the display on exit')
    args = parser.parse_args()

    # Create NeoPixel object with appropriate configuration.
    strip = PixelStrip(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, LED_BRIGHTNESS, LED_CHANNEL)
    # Intialize the library (must be called once before other functions).
    strip.begin()

    print('Press Ctrl-C to quit.')
    if not args.clear:
        print('Use "-c" argument to clear LEDs on exit')

    try:
        while True:
            print('Color wipe animations.')
            colorWipe(strip, Color(255, 255, 0))  # Red wipe
            colorWipe(strip, Color(0, 0, 0), 30)
            colorWipe(strip, Color(0, 255, 255))  # Blue wipe
            colorWipe(strip, Color(0, 0, 0), 30)
            colorWipe(strip, Color(255, 0, 255))  # Green wipe
            colorWipe(strip, Color(0, 0, 0), 30)
            
            print('Theater chase animations.')
            print('Rainbow animations.')
            rainbow(strip)
            colorWipe(strip, Color(0, 0, 0), 50)
            rainbowCycle(strip)
            colorWipe(strip, Color(0, 0, 0), 40)
            break
        while True:
            rainbowCycle(strip)
            #print('***********************')
            colorWipe(strip, Color(0, 0, 0), 100)

    except:
        colorWipe(strip, Color(0, 0, 0), 100)