1  // SPDX-FileCopyrightText: 2017 Mikey Sklar for Adafruit Industries
 2  //
 3  // SPDX-License-Identifier: MIT
 4  
 5  #include <Adafruit_NeoPixel.h>
 6  #define PIN 1
 7  #define NUM_LEDS 3
 8  
 9  Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);
10  
11  //                          R   G   B
12  uint8_t myColors[][5] = {
13                           {30, 144, 255},   // dodger blue
14                           {232, 100, 255},  // purple
15                           {204, 0, 204},    //  
16                           {200, 200, 20},   // yellow 
17                           {30, 200, 200},   // blue
18                           };
19                                 
20  // don't edit the line below
21  #define FAVCOLORS sizeof(myColors) / 5
22  
23  void setup() {
24    strip.begin();
25    strip.setBrightness(20);
26    strip.show(); // Initialize all pixels to 'off'
27  }
28  
29  void loop() {
30    flashRandom(10, 1);  // first number is 'wait' delay, shorter num == shorter twinkle
31    flashRandom(10, 3);  // second number is how many neopixels to simultaneously light up
32    flashRandom(10, 2);
33  }
34  
35  void flashRandom(int wait, uint8_t howmany) {
36   
37    for(uint16_t i=0; i<howmany; i++) {
38      // pick a random favorite color!
39      int c = random(FAVCOLORS);
40      int red = myColors[c][0];
41      int green = myColors[c][1];
42      int blue = myColors[c][2]; 
43   
44      // get a random pixel from the list
45      int j = random(strip.numPixels());
46      
47      // now we will 'fade' it in 5 steps
48      for (int x=0; x < 5; x++) {
49        int r = red * (x+1); r /= 5;
50        int g = green * (x+1); g /= 5;
51        int b = blue * (x+1); b /= 5;
52        
53        strip.setPixelColor(j, strip.Color(r, g, b));
54        strip.show();
55        delay(wait);
56      }
57      // & fade out in 5 steps
58      for (int x=5; x >= 0; x--) {
59        int r = red * x; r /= 5;
60        int g = green * x; g /= 5;
61        int b = blue * x; b /= 5;
62        
63        strip.setPixelColor(j, strip.Color(r, g, b));
64        strip.show();
65        delay(wait);
66      }
67    }
68    // LEDs will be off when done (they are faded to 0)
69  }