Clap Detector

/*

 This example reads audio data from an Invensense's ICS43432 I2S microphone

 breakout board, and uses the input to detect clapping sounds. An LED is

 togggled when a clapp is detected.

 Circuit:

 * Arduino Zero, MKRZero or MKR1000 board

 * ICS43432:

   * GND connected GND

   * 3.3V connected 3.3V (Zero) or VCC (MKR1000, MKRZero)

   * WS connected to pin 0 (Zero) or pin 3 (MKR1000, MKRZero)

   * CLK connected to pin 1 (Zero) or pin 2 (MKR1000, MKRZero)

   * SD connected to pin 9 (Zero) or pin A6 (MKR1000, MKRZero)

 created 18 November 2016

 by Sandeep Mistry

 */

#include <ArduinoSound.h>

// the LED pin to use as output

const int ledPin = LED_BUILTIN;

// the amplitude threshold for a clap to be detected

const int amplitudeDeltaThreshold = 100000000;

// create an amplitude analyzer to be used with the I2S input

AmplitudeAnalyzer amplitudeAnalyzer;

// variable to keep track of last amplitude
int lastAmplitude = 0;

void setup() {

  // setup the serial

  Serial.begin(9600);

  // configure the LED pin as an output

  pinMode(ledPin, OUTPUT);

  // setup the I2S audio input for 44.1 kHz with 32-bits per sample

  if (!AudioInI2S.begin(44100, 32)) {

    Serial.println("Failed to initialize I2S input!");

    while (1); // do nothing

  }

  // configure the I2S input as the input for the amplitude analyzer

  if (!amplitudeAnalyzer.input(AudioInI2S)) {

    Serial.println("Failed to set amplitude analyzer input!");

    while (1); // do nothing

  }
}

void loop() {

  // check if a new analysis is available

  if (amplitudeAnalyzer.available()) {

    // read the new amplitude

    int amplitude = amplitudeAnalyzer.read();

    // find the difference between the new amplitude and the last

    int delta = amplitude - lastAmplitude;



    // check if the difference is larger than the threshold

    if (delta > amplitudeDeltaThreshold) {

      // a clap was detected

      Serial.println("clap detected");



      // toggle the LED

      digitalWrite(ledPin, !digitalRead(ledPin));



      // delay a bit to debounce

      delay(100);

    }



    // update the last amplitude with the new amplitude

    lastAmplitude = amplitude;

  }
}