This is a sample code for Piano (Basic)'s Tutorial

piano.ino

/*
  This example code is for Piano(Basic)'s Tutorial.
  Product page:
  Maker UNO: https://www.cytron.io/p-maker-uno

  Created by:
  08/08/18  Suad Anwar, Cytron Technologies
*/

#include "pitches.h"

#define C  3
#define D  4
#define E  5
#define F  6
#define G  7
#define A  9
#define B  10
#define Buzzer  8

void setup()
{
  pinMode(C, INPUT_PULLUP);
  pinMode(D, INPUT_PULLUP);
  pinMode(E, INPUT_PULLUP);
  pinMode(F, INPUT_PULLUP);
  pinMode(G, INPUT_PULLUP);
  pinMode(A, INPUT_PULLUP);
  pinMode(B, INPUT_PULLUP);
}

void loop()
{
  while (digitalRead(C) == LOW)
  {
    tone(8, NOTE_C4);
  }

  while (digitalRead(D) == LOW)
  {
    tone(8, NOTE_D4);
  }

  while (digitalRead(E) == LOW)
  {
    tone(8, NOTE_E4);
  }

  while (digitalRead(F) == LOW)
  {
    tone(8, NOTE_F4);
  }

  while (digitalRead(G) == LOW)
  {
    tone(8, NOTE_G4);
  }

  while (digitalRead(A) == LOW)
  {
    tone(8, NOTE_A4);
  }

  while (digitalRead(B) == LOW)
  {
    tone(8, NOTE_B4);
  }

  noTone(8);

}