If you set the fourth value in the notes[] array to 392 instead of 349, that button will produce a G note instead of an F allowing you to play such killer shreds as Mary Had a Little Lamb and (the first couple lines of) Jingle Bells.
If you set the fourth value in the notes[] array to 392 instead of 349, that button will produce a G note instead of an F allowing you to play such killer shreds as Mary Had a Little Lamb and (the first couple lines of) Jingle Bells.