/*
 * Button Input pin D4 ~ D11 (INPUT_PULLUP)
 * Buzzer Pin D6
 */
#include "pitches.h"
#define buzzerPin 3

#define start_button 4
#define end_button 11


const uint16_t f[8] = {NOTE_C4, NOTE_D4, NOTE_E4,
                      NOTE_F4,NOTE_G4,NOTE_A4, NOTE_B4, NOTE_C5};

void setup() {
  Serial.begin(9600);
  for(int i = start_button ; i <= end_button ; i++){
    pinMode(i, INPUT_PULLUP);
  }
}

void loop() {
  for(int i = start_button ; i <= end_button ; i++){
    if(digitalRead(i) == LOW){
      tone(buzzerPin, f[i-start_button], 100);
    }
  }
}