Wings.ino

#include <Adafruit_NeoPixel.h>

#define N_PIXELS  5     // Number of pixels in strand
#define LED_PIN1  6     // 1 = RIGHT
#define LED_PIN2  12    // 2 = LEFT

Adafruit_NeoPixel strip1 = Adafruit_NeoPixel(N_PIXELS, LED_PIN1, NEO_GRB + NEO_KHZ800);
Adafruit_NeoPixel strip2 = Adafruit_NeoPixel(N_PIXELS, LED_PIN2, NEO_GRB + NEO_KHZ800);

// Adapted from https://learn.adafruit.com/ursulas-seashell-necklace/the-code
#define MIC_PIN A9             // Analog port for microphone
#define DC_OFFSET  0           // DC offset in mic signal - if unusure, leave 0
#define NOISE     100          // 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 (N_PIXELS + 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 "dampened" audio level
    minLvlAvg = 0,             // For dynamic adjustment of graph low & high
    maxLvlAvg = 512;

void setup() {
  
  // start the LEDs at 'off' and start the volume array at '0' in case there is anything left over from previous run
  memset(vol, 0, sizeof(vol)); // See http://www.cplusplus.com/reference/cstring/memset/

  strip1.begin();    
  strip2.begin();  

}

void loop() {

  // Declare variables for doing the mic math
  uint8_t  i;               // uint8_t = unsigned byte (remains 8 bits on any system)
  uint16_t minLvl, maxLvl;  // uint16_t = unsigned 2 byte integer (remains 16 bits on any system)
  int      n, height;

  // Rather than using a Mic Library, this example uses raw math (that I do not follow):
  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 (see https://www.tutorialspoint.com/cprogramming/c_operators.htm)
  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);

  // Constrain the lights to the top and bottom of the LED strip
  if(height < 0L) height = 0;           // Clip output
  else if(height > TOP) height = TOP;
  if(height > peak) peak = height;      // Keep 'peak' at top

  // Color pixels based on rainbow gradient - Wheel() cycles through all the colors
  for(i = 0; i < N_PIXELS; i++) {
    if(i >= height) {
      strip1.setPixelColor(i, 0, 0, 0);
      strip2.setPixelColor(i, 0, 0, 0);
    }
    // Change the last two values to change the colors that the pixels cycle thru
    else {
      strip1.setPixelColor(i, Wheel(map(i, 0, strip1.numPixels()-1, 30, 150)));
      strip2.setPixelColor(i, Wheel(map(i, 0, strip2.numPixels()-1, 30, 150)));
    }
  }

  // Draw peak dot  
  if(peak > 0 && peak <= N_PIXELS-1) {
    strip1.setPixelColor(peak,Wheel(map(peak,0,strip1.numPixels()-1,30,150)));
    strip2.setPixelColor(peak,Wheel(map(peak,0,strip2.numPixels()-1,30,150)));
  }
  
  strip1.show();
  strip2.show();
              
}


// Define Wheel()
//  - Input a value 0 to 255 to get a color value.
//  - The colors are a transition r - g - b - back to r.
//  - WheelPos = the value of whereever the LED color is on the 0-255 scale
uint32_t Wheel(byte WheelPos) {
  if(WheelPos < 85) {
   return strip1.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
//   return strip2.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
  } else if(WheelPos < 170) {
   WheelPos -= 85;
   return strip1.Color(255 - WheelPos * 3, 0, WheelPos * 3);
//   return strip2.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  } else {
   WheelPos -= 170;
   return strip1.Color(0, WheelPos * 3, 255 - WheelPos * 3);
//   return strip2.Color(0, WheelPos * 3, 255 - WheelPos * 3);  
  }
} // Wheel()