In this tutorial, I will discuss how make Arduino play your favorite melody. There is a nice tutorial which illustrate the basic process here. But to play your favourite melody you will have to get the combination of notes, durations of individual notes and pauses as precise as possible. In this tutorial, I will discuss how to develop a sketch for Arduino to play custom melodies and way to test the sketch on your PC before writing it to Arduino board.

• Piano notes for your melody.
• This example as the starting point for the sketch.
• PC program to test your note sequence. (read on ..!)

Finding notes for your melody/tune
If you can play it on piano, you can easily write them down on paper. If not, then you can search for notes on the web. For this example, I would be using very simple melody containing following notes:

cdf dfg fga gab abc#
(plays piano keys in this fashion: 123,234,345,456,567)

Writing your sketch
I would advise using the same sketch as mentioned here: http://arduino.cc/en/Tutorial/Tone. However, we are not going to directly modify this sketch. Notice the array 'melody' and 'noteDurations' in the C code. What we need to do, is find correct elements and their sequence for these two arrays. This is not an easy task and at some point you will always feel the need of a simulator where you could test your compilation. This is where we create a PC program to test note sequence.

Creating PC program to test note compilation
I am using C# to write a simple program (similar to one in example) to test my notes compilation. This program uses PC speakers to generate sound and gives a fair idea of what the notes will sound with Arduino. Also, it is very easy to modify and fine tune your compilation using the C# program.

This is how the array values looks like in the C# program for the melody I selected:

 			//Play the following notes
            //cdf dfg fga gab abc#
            int[] melody = new int[] { NOTE_C4,0,NOTE_D4,0,NOTE_F4,0,
                                       NOTE_D4,0,NOTE_F4,0,NOTE_G4,0,
                                       NOTE_F4,0,NOTE_G4,0, NOTE_A4,0,
                                       NOTE_G4,0,NOTE_A4,0, NOTE_B4,0,
                                       NOTE_A4,0,NOTE_B4,0, NOTE_C5,0};

            int[] noteDurations = new int[] { 8,8,8,8,8,4,
                                              8,8,8,8,8,4,
                                              8,8,8,8,8,4,
                                              8,8,8,8,8,4,
                                              8,8,8,8,8,4};


            for (int thisNote = 0; thisNote < 30; thisNote++)
            {
                int noteDuration = 1000 / noteDurations[thisNote];
                if (melody[thisNote] > 0)
                    Console.Beep(melody[thisNote], noteDuration);
                else
                    System.Threading.Thread.Sleep(noteDuration);
            }

int melody[] = { NOTE_C4,0,NOTE_D4,0,NOTE_F4,0,
                 NOTE_D4,0,NOTE_F4,0,NOTE_G4,0,
                 NOTE_F4,0,NOTE_G4,0, NOTE_A4,0,
                 NOTE_G4,0,NOTE_A4,0, NOTE_B4,0,
                 NOTE_A4,0,NOTE_B4,0, NOTE_C5,0};

// note durations: 4 = quarter note, 8 = eighth note, etc.:
int noteDurations[] = { 8,8,8,8,8,4,
                        8,8,8,8,8,4,
                        8,8,8,8,8,4,
                        8,8,8,8,8,4,
                        8,8,8,8,8,4};

for (int thisNote = 0; thisNote < 30; thisNote++) {

Finally
I hope this tutorial will help you play your favorite melody with Arduino. The approach which I described in this article should work almost all types of microcontrollers. If you know better tools to do this, please drop a me a comment. Suggestions and criticism are always welcomed (as I am very new to Arduino).