Arduino_Disco_Ball_Cake.ino

/* ==================================================================================================================================================
                Project: Arduino Disco Ball Cake
            LED chipset: ws2812B  (IC Station item ID: 5248): http://goo.gl/uDQjZW
                 Author: Scott C
                Created: 2nd June 2016
            Arduino IDE: 1.6.4
FastLED library version: 3.0.3
                Website: http://arduinobasics.blogspot.com/p/arduino-basics-projects-page.html
            Description: Create a random LED sequence - Disco effect
                         FastLED library information at http://fastled.io/  
                         FastLED library download from: https://github.com/FastLED/FastLED/
====================================================================================================================================================*/

#include "FastLED.h"  // Requires the FastLED library

#define NUM_LEDS 64   // This is the number of LEDs in total. 1 ring = 16 LEDS, 2 rings = 32 LEDs, 4 rings = 64 LEDs. Change this value according to the number of LEDs in use.
#define DATA_PIN 9    // Digital pin 9 (D9) on Arduino will be connected to "Din" on LED ring. This LED ring only requires a Data line (no clock required). 

byte hue = 0;         // This variable will control the hue of the LEDs
int rnd = 0;          // A variable used to hold a random number
CRGB leds[NUM_LEDS];  // Create an Array of LEDs

void setup() { 
  FastLED.addLeds<NEOPIXEL,DATA_PIN>(leds, NUM_LEDS);  //Initialise the LED ring(s)
}

void loop() {  
    hue=hue+5;                            //Change the Hue slightly with every loop (makes a progressive rainbow effect)
    randomSeed(analogRead(A0));           //Using a floating Analog Pin to provide better randomisation 
    rnd = random8(NUM_LEDS);              //Randomly choose one of the LEDs
    leds[rnd].setHSV(hue,255,255);        //Set the randomly chosen LED to illuminate when "FastLED.show();" is called
    FastLED.show();                       //Update the LEDs to display the modified LED sequence.
    delay(50);                            //The time between LED flashes. This is pretty quick. i.e. 20 flashes per second.
    
    for(int i=0; i<NUM_LEDS; i++){
      leds[i].fadeToBlackBy( 180 );       //Fade every LED by 180. Increase this number to make the LEDs fade faster
    } 
    FastLED.show();                       //Update the LEDs to display the modified LED sequence
}