View source for Programmable LEDs

= LED strip =

* RS product: https://se.rs-online.com/web/p/led-ljuslister/1807500?gb=s
** Datasheet: https://docs.rs-online.com/c4c2/0900766b816d3d12.pdf

== Dependencies == 
* Install the library FastLED: https://github.com/FastLED/FastLED 
** Documentation: https://github.com/FastLED/FastLED/wiki/Overview
** Basic usage: https://github.com/FastLED/FastLED/wiki/Basic-usage

== Examples online ==
* https://learn.adafruit.com/adafruit-neopixel-uberguide/the-magic-of-neopixels
* https://create.arduino.cc/projecthub/whimsy-makerspace/arduino-compatible-nano-neopixel-controller-6f0c4b

== How to use == 

[[File:Fastled-library.png|thumb]]

Install the FastLED library in the Arduino IDE.

=== How to connect the LED strip ===

Make sure the arrows are pointing to the right direction. The beginning of an arrow indicates the connection point to the Arduino board.  The tip of the arrow show how the current flows in the strip.

[[File:Fastled-connect bb.png|thumb]]

=== Source code ===
<pre>
// include library
#include<FastLED.h>

//define number of LED and pin
#define NUM_LEDS 4
#define DATA_PIN 3

// create the ld object array
CRGB leds[NUM_LEDS];

// define 3 byte for the random color
byte  r, g, b;
float brightness;

void setup() {
  Serial.begin(9600);
  // init the LED object
  FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
  // set random seed
  randomSeed(analogRead(0));
}

void loop() {
  // loop over the NUM_LEDS
  for (int cur = 0; cur < NUM_LEDS; cur++) {
    brightness = 50.0 / pow(2, cur);
    FastLED.setBrightness(brightness); // range: 0-255
    r = random(150, 200);
    g = random(100, 150);
    b = random(0, 50);
    //set the value to the led AND turn on
    leds[cur] = CRGB(r, g, b); FastLED.show();
    FastLED.delay(200);
    // turn off previous
    leds[cur] = CRGB::Black; FastLED.show();
    Serial.println(cur, DEC);
  }
} 
</pre>