KnockTest

/* This code has been adapted from the
 * Example Sound Level Sketch for the
 * Adafruit Microphone Amplifier 
 */
#include <Adafruit_NeoPixel.h>
#define PIN 6
#define NUM_LIGHTS  25
Adafruit_NeoPixel strip = Adafruit_NeoPixel(60, PIN, NEO_GRB + NEO_KHZ800);
const int sampleWindow = 250; // Sample window width in mS (250 mS = 4Hz)
unsigned int knock;
int ledPin = 6;

void setup() 
{
  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
  strip.begin();
  strip.show(); // Initialize all pixels to 'off'
}

void loop() 
{
 uint32_t low = strip.Color(0, 0, 0); 
 uint32_t high = strip.Color(255, 255, 255);
 unsigned long start= millis();  // Start of sample window
 unsigned int peakToPeak = 0;   // peak-to-peak level

 unsigned int signalMax = 0;
 unsigned int signalMin = 1024;

 // collect data for 250 miliseconds
 while (millis() - start < sampleWindow)
 {
   knock = analogRead(0);
      if (knock < 1024)  //This is the max of the 10-bit ADC so this loop will include all readings
      {
         if (knock > signalMax)
         {
           signalMax = knock;  // save just the max levels
         }
      else if (knock < signalMin)
        {
         signalMin = knock;  // save just the min levels
         }
     }
 }
 peakToPeak = signalMax - signalMin;  // max - min = peak-peak amplitude
 double volts = (peakToPeak * 3.3) / 1024;  // convert to volts


Serial.println(volts);
 if (volts >=1.0)
 {
  //turn on LED
  for( int i = 0; i<NUM_LIGHTS; i++){
        strip.setPixelColor(i, high);
        strip.show();
    }   
    delay(100);
  Serial.println("Knock Knock");
 }
 else
 {
for( int i = 0; i<NUM_LIGHTS; i++){
        strip.setPixelColor(i, low);
        strip.show();
    }   
     delay(100);
 }             
}