Simple_circle.ino

/* Simple FastLED circle
 *
 *
 */

#include <FastLED.h>                                          // FastLED library.

#ifdef ESP8266
#define FASTLED_ALLOW_INTERRUPTS 0                            // Used for ESP8266 with WS2812 LED's. Ugh!!!
#endif

// Fixed definitions cannot change on the fly.
#define LED_DT D4                                             // Data pin to connect to the strip.
#define COLOR_ORDER GRB                                       // It's GRB for WS2812 and BGR for APA102.
#define LED_TYPE WS2812
#define NUM_LEDS 30                                           // Number of LED's.

uint8_t max_bright = 64;                                      // Overall brightness definition. It can be changed on the fly.

struct CRGB leds[NUM_LEDS];                                   // Initialize our LED array.


void setup() {
  LEDS.addLeds<LED_TYPE, LED_DT, COLOR_ORDER>(leds, NUM_LEDS);  // Use this for WS2812
  FastLED.setBrightness(max_bright);
} // setup()


void loop() {
  fadeToBlackBy(leds, NUM_LEDS, 4);      // Smaller value = longer tail
  int i = (millis()/40) % NUM_LEDS;      // How fast it goes.
  leds[i] = CRGB::White;
  FastLED.show();
}