#define NUM_STRIPS 2
#define NUM_LEDS_PER_STRIP 500

#include "FastLED.h"

FASTLED_USING_NAMESPACE

#define NUM_LEDS NUM_LEDS_PER_STRIP * NUM_STRIPS
#define LED_TYPE    WS2812

CRGB leds[NUM_STRIPS * NUM_LEDS_PER_STRIP];

void setup() {
  FastLED.addLeds<LED_TYPE, 13>(leds, 0, NUM_LEDS_PER_STRIP);
}

void loop()
{
  for( int f = 0; f < 160; f++){
    leds[f] = CRGB(f, f, f);
  }
  delay(100);
  FastLED.show();
  FastLED.clearData();
  delay(100);
  FastLED.show();
}