#include <neopixel.h>

// IMPORTANT: Set pixel COUNT, PIN and TYPE
#define PIXEL_PIN D2
#define PIXEL_COUNT 16
#define PIXEL_TYPE WS2812
 
Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXEL_COUNT, PIXEL_PIN, PIXEL_TYPE);

void setup() {
    strip.begin();

}

void loop() {
    uint32_t white = strip.Color(255, 255, 255);
    uint32_t black = strip.Color(0, 0, 0);
    
    int numPixels = strip.numPixels();
    
    for( int i = 0; i < numPixels; i++ ){
        strip.setPixelColor(i, white); // set a color 
        
        strip.show();
        delay(500);
        
        strip.setPixelColor(i, black); // remove the color
        strip.show();
        delay(500);
    }
}