Before You Start

If this is your first foray into the world of arduino-based microcontrollers, you'll need to install some software first. Head over to the Circuit Playground Lesson 0 guide for detailed installation and setup instructions.  

You'll only need to do all this once, so be a little patient if it seems like a lot!

FastLED Library

You will also need to install the FastLED library in Arduino (Sketch > Include Library > Manage Libraries...)

One other note:  if you're using FastLED with Circuit Playground, be sure to #include the Circuit Playground library FIRST and the FastLED library second, or you may run into problems.

Upload Code

Once you've got everything installed and your computer can talk to the Circuit Playground, it's time to upload the code.

Plug your Circuit Playground into your computer and select the Circuit Plaground under Tools > Boards.  Then select the Circuit Playground as the Port.

Copy and paste this code into a new Arduino window and click "upload".

// Code by Erin St Blaine for Adafruit.com
// Full tutorial at https://learn.adafruit.com/glowing-beehive-hairdo-wig/

#include <Adafruit_CircuitPlayground.h>  // add this before the FastLED library to avoid issues
#include <FastLED.h>

#define LED_PIN     6    //led strand is soldered to pin 6
#define CP_PIN      17   //circuit playground's neopixels live on pin 17
#define NUM_LEDS    12   // number of LEDs in my strand
#define NUM_CP      10   // number of neopixels on the circuit playground

// I have purposefully mixed up the color order on the Neopixel strip to 
// quickly and easily add color variety to this code -- This way the strip will always
// show a different color from the light pipe. 

#define COLOR_ORDER GRB   
#define COLOR_ORDER_STRIP  RBG 

uint8_t brightness = 255;  //led strand brightness control
uint8_t cpbrightness = 255;  //circuit playground brightness control

int STEPS = 25;  //makes the rainbow colors more or less spread out
int NUM_MODES = 4;  // change this number if you add or subtract modes

CRGB leds[NUM_LEDS];  //I've set up different arrays for the neopixel strand and the circuit playground
CRGB cp[NUM_CP];      // so that we can control the brightness separately

CRGBPalette16 currentPalette;
TBlendType    currentBlending;

int ledMode = 0;       //Initial mode 
bool leftButtonPressed;
bool rightButtonPressed;

// SOUND REACTIVE SETUP --------------

#define MIC_PIN         A4                                    // Analog port for microphone
#define DC_OFFSET  0                                          // DC offset in mic signal - if unusure, leave 0
                                                              // I calculated this value by serialprintln lots of mic values
#define NOISE     200                                         // Noise/hum/interference in mic signal and increased value until it went quiet
#define SAMPLES   60                                          // Length of buffer for dynamic level adjustment
#define TOP (NUM_LEDS + 2)                                    // Allow dot to go slightly off scale
#define PEAK_FALL 10                                          // Rate of peak falling dot
 
byte
  peak      = 0,                                              // Used for falling dot
  dotCount  = 0,                                              // Frame counter for delaying dot-falling speed
  volCount  = 0;                                              // Frame counter for storing past volume data
int
  vol[SAMPLES],                                               // Collection of prior volume samples
  lvl       = 10,                                             // Current audio level, change this number to adjust sensitivity
  minLvlAvg = 0,                                              // For dynamic adjustment of graph low & high
  maxLvlAvg = 512;


// SETUP -------------------

void setup() {
  Serial.begin(57600);
  CircuitPlayground.begin();
  FastLED.addLeds<WS2812B, LED_PIN, COLOR_ORDER_STRIP>(leds, NUM_LEDS).setCorrection( TypicalLEDStrip );
  FastLED.addLeds<WS2812B, CP_PIN, COLOR_ORDER>(cp, 10).setCorrection( TypicalLEDStrip );
  currentBlending = LINEARBLEND;
  set_max_power_in_volts_and_milliamps(5, 500);               // FastLED 2.1 Power management set at 5V, 500mA

  
}

void loop()  {

  leftButtonPressed = CircuitPlayground.leftButton();
  rightButtonPressed = CircuitPlayground.rightButton();

  if (leftButtonPressed) {  //left button cycles through modes
    clearpixels(); 
    ledMode=ledMode+1;
    delay(300);
    if (ledMode > NUM_MODES){
    ledMode=0;
     }
  }
    if (rightButtonPressed) {   // right button turns all leds off
    ledMode=99;
  
    }
  
 switch (ledMode) {
       case 0: currentPalette = RainbowColors_p; rainbow(); break; 
       case 1: soundreactive(); break; 
       case 2: currentPalette = OceanColors_p; rainbow(); break;                    
       case 3: currentPalette = LavaColors_p; rainbow(); break; 
       case 4: currentPalette = RainbowStripeColors_p; rainbow(); break;    
       case 99: clearpixels(); break;
       
}
}

void clearpixels()
{
  CircuitPlayground.clearPixels();
  for (int i = 0; i < NUM_LEDS; i++) leds[i] = CRGB::Black; 
  for (int i = 0; i < NUM_CP; i++) cp[i] = CRGB::Black;
  FastLED.show();
}

void rainbow()
{
  
  static uint8_t startIndex = 0;
  startIndex = startIndex + 1; /* motion speed */

  FillLEDsFromPaletteColors( startIndex);

  FastLED.show();
  FastLED.delay(20);}

//this bit is in every palette mode, needs to be in there just once
void FillLEDsFromPaletteColors( uint8_t colorIndex)
{ 
  for (int i = 0; i < NUM_LEDS; i++) leds[i] = ColorFromPalette( currentPalette, colorIndex, brightness, currentBlending);
  for (int i = 0; i < NUM_CP; i++) cp[i] = ColorFromPalette( currentPalette, colorIndex, cpbrightness, currentBlending);
    colorIndex += 25;
  
}


void soundreactive() {

  uint8_t  i;
  uint16_t minLvl, maxLvl;
  int      n, height;
   
  n = analogRead(MIC_PIN);                                    // Raw reading from mic
  n = abs(n - 512 - DC_OFFSET);                               // Center on zero
  
  n = (n <= NOISE) ? 0 : (n - NOISE);                         // Remove noise/hum
  lvl = ((lvl * 7) + n) >> 3;                                 // "Dampened" reading (else looks twitchy)
 
  // Calculate bar height based on dynamic min/max levels (fixed point):
  height = TOP * (lvl - minLvlAvg) / (long)(maxLvlAvg - minLvlAvg);
 
  if (height < 0L)       height = 0;                          // Clip output
  else if (height > TOP) height = TOP;
  if (height > peak)     peak   = height;                     // Keep 'peak' dot at top
 
 
  // Color pixels based on rainbow gradient -- led strand
  for (i=0; i<NUM_LEDS; i++) {
    if (i >= height)   leds[i].setRGB( 0, 0,0);
    else leds[i] = CHSV(map(i,0,NUM_LEDS-1,0,255), 255, brightness);  //constrain colors here by changing HSV values
  }
 
  // Draw peak dot  -- led strand
  if (peak > 0 && peak <= NUM_LEDS-1) leds[peak] = CHSV(map(peak,0,NUM_LEDS-1,0,255), 255, brightness);

  // Color pixels based on rainbow gradient  -- circuit playground
  for (i=0; i<NUM_CP; i++) {
    if (i >= height)   cp[i].setRGB( 0, 0,0);
    else cp[i] = CHSV(map(i,0,NUM_CP-1,0,255), 255, cpbrightness);  //constrain colors here by changing HSV values
  }
 
  // Draw peak dot  -- circuit playground
  if (peak > 0 && peak <= NUM_CP-1) cp[peak] = CHSV(map(peak,0,NUM_LEDS-1,0,255), 255, cpbrightness);

// Every few frames, make the peak pixel drop by 1:
 
    if (++dotCount >= PEAK_FALL) {                            // fall rate 
      if(peak > 0) peak--;
      dotCount = 0;
    }
  
  vol[volCount] = n;                                          // Save sample for dynamic leveling
  if (++volCount >= SAMPLES) volCount = 0;                    // Advance/rollover sample counter
 
  // Get volume range of prior frames
  minLvl = maxLvl = vol[0];
  for (i=1; i<SAMPLES; i++) {
    if (vol[i] < minLvl)      minLvl = vol[i];
    else if (vol[i] > maxLvl) maxLvl = vol[i];
  }
  // minLvl and maxLvl indicate the volume range over prior frames, used
  // for vertically scaling the output graph (so it looks interesting
  // regardless of volume level).  If they're too close together though
  // (e.g. at very low volume levels) the graph becomes super coarse
  // and 'jumpy'...so keep some minimum distance between them (this
  // also lets the graph go to zero when no sound is playing):
  if((maxLvl - minLvl) < TOP) maxLvl = minLvl + TOP;
  minLvlAvg = (minLvlAvg * 63 + minLvl) >> 6;                 // Dampen min/max levels
  maxLvlAvg = (maxLvlAvg * 63 + maxLvl) >> 6;                 // (fake rolling average)


show_at_max_brightness_for_power();                         // Power managed FastLED display
  Serial.println(LEDS.getFPS()); 
} 

If all goes well, the lights on the Circuit Playground will come on.  Press the right side button and the lights will go off.  Press the left side button to toggle between modes:

  1. Rainbow Colors
  2. Sound Reactive
  3. Ocean Colors
  4. Lava Colors
  5. Rainbow Stripe Colors

Press the button once to enter Sound Reactive mode.  Make some noise!   

Add your own modes or customize the modes that are already there.  If you add more modes, remember to change the NUM_MODES variable to reflect the total number of modes you have.

This guide was first published on Oct 06, 2017. It was last updated on Oct 06, 2017. This page (Code) was last updated on Oct 02, 2017.