CPP: NeoPixels

NeoPixels, also known as WS2812b LEDs, are full-colour LEDs that are connected in serial, are individually addressable, and can have their red, green and blue components set between 0 and 255. They require precise timing to control them and there is a special neopixel module to do just this.

Schematic

Download the project

Checkout this PlatformIO project code here

Libs installation

We need the Neopixel Adafruit library, but it is easy with PlatformIO from command line:

$ platformio lib install https://github.com/adafruit/Adafruit_NeoPixel.git
Library Storage: /home/lvidarte/Projects/esp8266/NeoPixels/.piolibdeps
LibraryManager: Installing Adafruit_NeoPixel
git version 2.7.4
Cloning into '/home/lvidarte/Projects/esp8266/NeoPixels/.piolibdeps/installing-tuhmeX-package'...
remote: Counting objects: 23, done.
remote: Compressing objects: 100% (22/22), done.
remote: Total 23 (delta 1), reused 11 (delta 0), pack-reused 0
Unpacking objects: 100% (23/23), done.
Checking connectivity... done.

Code

#include <Arduino.h>
#include <Adafruit_NeoPixel.h>

#define NUM_PIXELS 10
#define PIN_PIXELS 14

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUM_PIXELS, PIN_PIXELS, NEO_GRB + NEO_KHZ800);

void setup ()
{
  pixels.begin();
}

void loop ()
{
  int i;
  for (i = 0; i < NUM_PIXELS; i++)
  {
    pixels.setPixelColor(i, pixels.Color(127, 0, 0));
    pixels.show();
    delay(500);
  }

  for (i = NUM_PIXELS - 1; i >= 0; i--)
  {
    pixels.setPixelColor(i, pixels.Color(0, 127, 0));
    pixels.show();
    delay(500);
  }
}