NeoPixel(WS2812)

A single LED that can display multiple colors by adjusting RGB values, with each LED individually controllable by a controller.

In the text, two models were used: a circular one with 7 LEDs and a linear one with 8 LEDs.

The terminals total either 6 or 8, with the 6-terminal version comprising (IN, 2x VCC, 2x GND, OUT), and the 8-terminal version adding 2 more GNDs to the 6-terminal setup.

Connecting the OUT terminal of a NeoPixel to the IN terminal of the next allows for controlling multiple NeoPixels with just one pin on the board.

Specifications

Operating Voltage: 5V
Current per LED: 20mA ~ 80mA

Required Hardware

NeoPixel
Arduino UNO
UNO cable
M-M cable(6ea)
F-M cable(3ea)

Connection (M-M and F-M cables were soldered for connection to the NeoPixel)

NeoPixel to Arduino Connection


NeoPixel	Arduino
IN	D7
VCC	5V
GND	GND

Connection between the 1st and 2nd NeoPixel (apply the same method to add more NeoPixels):


1st NeoPixel	2nd NeoPixel
OUT	IN
VCC	VCC
GND	GND

Library

Adafruit NeoPixel (Arduino Libraries)

예제 코드

#include <Adafruit_NeoPixel.h>

// Using pin number 7
#define PIN        7
// Number of pixels
#define NUMPIXELS 15
// Brightness level
#define bright 255
#define dly 10000
// Create a NeoPixel object for control
Adafruit_NeoPixel neo(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

void setup() {
    // Start NeoPixel
    neo.begin();
    // Set NeoPixel brightness
    neo.setBrightness(bright);
    // Initialize NeoPixel
    neo.clear();
    // Apply NeoPixel settings
    // Settings are applied internally until .show() is executed.
    // When .show() runs, the commands applied internally are executed on the LEDs.
    neo.show();
}

void loop()
{
    // Turn LEDs white
    for (int i = 0; i < 15; i++)
    {
        neo.setPixelColor(i, 255, 255, 255);
    }
    neo.show();
    delay(500);

    // Turn LEDs red
    for (int i = 0; i < 15; i++)
    {
        neo.setPixelColor(i, 255, 0, 0);
    }
    neo.show();
    delay(500);

    // Turn LEDs green
    for (int i = 0; i < 15; i++)
    {
        neo.setPixelColor(i, 0, 255, 0);
    }
    neo.show();
    delay(500);

    // Turn LEDs blue
    for (int i = 0; i < 15; i++)
    {
        neo.setPixelColor(i, 0, 0, 255);
    }
    neo.show();
    delay(500);
}

Execution Result