Controlling WS2812b LED lights using Flask webserver with Raspberry Pi!

REQUIREMENTS

Hardware

Raspberry PI (3 or later recommended)
WS2812b LED Lights (30pixels/m, 150 LEDs) Amazon
5V 10a Power Supply Amazon- comes with a DC Barrel Jack to 2-Pin Terminal Block Adapter
Male-to-female jumper wire connectors for connecting GPIO pins to LEDs

Software

I recommend making a new directory for this project and activating a virtual environment for all the packages

Make sure you sudo apt update and sudo apt upgrade
Also, make sure pip is up to date otherwise you will have package issues pip install --upgrade pip
Python version must be above 3.6 -check what python version you have with python3 --version in the terminal

These are the packages you will be installing:

sudo pip3 install rpi_ws281x
sudo pip3 install adafruit-circuitpython-neopixel

If there's an error try pip instead of pip3 otherwise everything should be good to go

WS2812b LED Lights

Every type of WS2812b LED lights take 5V
Each Pixel on the Strip has 3 individual LEDs for Red, Green, and Blue which each take up 20miliamps at max brightness

This project requires:

9amps = 0.06amps x 150 LEDS
5v

Choose your power supply based on the number of LEDs
General Tip: 30pixels/m have LEDS much more spread out per meter than 60pixels/m

Hardware Connections

Connect the negative(white) and the positive(red) wire to the DC barrel jack and screw it down -the jack should have (+) and (-) labels to ensure you are putting wires in the right terminal
Connect the male side of the white jumper wire to the white wire port of the LED strip
Connect the male side of the green jumper wire to the green wire port of the LED strip
Connect the female side of the white jumper wire to the ground pin of the Raspberry Pi (Physical Pin #6)
Connect the female side of the green jumper wire to GPIO pin number 18

Notice there is no red wire connected to Raspberry Pi this is because the LED lights are getting power from the 5v power supply instead of the Raspberry Pi

Setting Up a Flask Webserver

I recommend having basic knowledge of Flask and checking out this Flask Tutorial on YouTube

You can use any editor of your choice, but please ensure it's in the directory you want it to be in. For this project, I kept the Flask script inside the "Flask_Webserver_LEDlights" directory

To set up a basic Flask Webserver:

from flask import Flask

app = Flask(__name__)

@app.route("/")
def home():
    return "hello home"

if __name___ == "__main__"
    app.run()

Controlling the LED Lights

Outside the Flask Directory, I had a different set of scripts that tested the functionality of the GPIO pins and LED strip. The first way I tested the functionality was with the strandtest.py script which I got from Core Electronics

Copy and paste the code and try it for yourself!

Make sure you edit the LED_COUNT = 150 line to match the number of LEDs you have in your strip
Make sure LED_PIN = 18 is the right pin number

This is the original code:

#!/usr/bin/env python3
# NeoPixel library strandtest example
# Author: Tony DiCola (tony@tonydicola.com)
#
# Direct port of the Arduino NeoPixel library strandtest example.  Showcases
# various animations on a strip of NeoPixels.

import time
from rpi_ws281x import *
import argparse

# LED strip configuration:
LED_COUNT      = 30     # Number of LED pixels.
LED_PIN        = 18      # GPIO pin connected to the pixels (18 uses PWM!).
#LED_PIN        = 10      # GPIO pin connected to the pixels (10 uses SPI /dev/spidev0.0).
LED_FREQ_HZ    = 800000  # LED signal frequency in hertz (usually 800khz)
LED_DMA        = 10      # DMA channel to use for generating a signal (try 10)
LED_BRIGHTNESS = 65      # 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



# Define functions which animate LEDs in various ways.
def colorWipe(strip, color, wait_ms=50):
    """Wipe color across display a pixel at a time."""
    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):
    """Movie theater light style chaser animation."""
    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):
    """Generate rainbow colors across 0-255 positions."""
    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):
    """Draw rainbow that fades across all pixels at once."""
    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=20, iterations=5):
    """Draw rainbow that uniformly distributes itself across all pixels."""
    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):
    """Rainbow movie theater light style chaser animation."""
    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 = Adafruit_NeoPixel(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, 0, 0))  # Red wipe
            colorWipe(strip, Color(0, 255, 0))  # Blue wipe
            colorWipe(strip, Color(0, 0, 255))  # Green wipe
            print ('Theater chase animations.')
            theaterChase(strip, Color(127, 127, 127))  # White theater chase
            theaterChase(strip, Color(127,   0,   0))  # Red theater chase
            theaterChase(strip, Color(  0,   0, 127))  # Blue theater chase
            print ('Rainbow animations.')
            rainbow(strip)
            rainbowCycle(strip)
            theaterChaseRainbow(strip)

    except KeyboardInterrupt:
        if args.clear:
            colorWipe(strip, Color(0,0,0), 10)

You can customize the while True statement at the end of the script for your personalization
The strandtest.py in this repository has been customized for my liking. Go check it out!

Neopixel

The neopixel library is a different library to individually customize each pixel on the strip

Neopixel does require root access so make sure you have that

To turn on the first pixel of your strip check out the OneLEDLightup.py script or copy this code:

import board
import neopixel
import time
pixels = neopixel.NeoPixel(board.D18, 150)

pixels[0] = (255, 20, 20)
time.sleep(5)
pixels[0] = (0,0,0)

Make sure pixels = neopixel.NeoPixel(board.D18, 150) is the right number pin(D18) and the right number of LEDs (150) You can change the RBG color values to your choice!

Combining Flask and LEDs

Inside your directory:

Create the Python Script for the Flask web server
create a templates folder to reference the HTML files
create a static folder to reference the CSS files

The ControlLED.py script effectively combines flask and strandtest.py into one but there are a few key components to make correct

color = request.form["color"] the variable must match the HTML "name" element of the buttons
For example, color matches the name="color" value

<form action="#" method="post">
             <button class="Button" id="red" name="color" value="red" type="submit">Red</button>
     </form>

if color == "red": for each "if" statement, color must equal the value element of the HTML file as you can see above

This isn't the most efficient way of handling multiple POST requests especially if you have multiple sources of requests. For this project, it's simple and very easy to learn

An efficient way of handling multiple requests would be an API

Customize your website using HTML and CSS

This is an example of what my website looked like!

WS2812b LED lights in Action!

Helpful Links

Control Multiple Fully-Addressable WS2812B RGB LED Strips with a Raspberry Pi Single Board Computer
Learn to Program Custom LED Lights
CONTROLLING WS2812B LEDS WITH A RASPBERRY PI
Flask Youtube Tutorials
AdaFruit NeoPixel Github
NeoPixel on Raspberry Pi

shaanCh / Controlling-LEDs-RaspberryPi-Webserver