#include <Adafruit_NeoPixel.h>

#define PIN        2
#define NUMPIXELS 16
#define DELAYVAL 500

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, 2);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");

  pixels.begin();
}

void loop() {
  // put your main code here, to run repeatedly:
  pixels.clear();
  pixels.show();
  delay(DELAYVAL);
  for(int i=0; i<NUMPIXELS; i++) {

    pixels.setPixelColor(i, pixels.Color(0, 150, 0));
    pixels.show();
    delay(DELAYVAL);
  }
}