#include <Adafruit_NeoPixel.h>

#define LED_PIN 8
#define LED_COUNT 1

Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);

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

void loop() {
  for (int i = 0; i < 256; i++) {
    for (int j = 0; j < strip.numPixels(); j++) {
      strip.setPixelColor(j, Wheel((i + j) & 255));
    }
    strip.show();
    delay(20);
  }
}

uint32_t Wheel(byte WheelPos) {
  if (WheelPos < 85) {
    return strip.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
  } else if (WheelPos < 170) {
    WheelPos -= 85;
    return strip.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  } else {
    WheelPos -= 170;
    return strip.Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
}