Hello dear chang
see below:

DO
DO#
RE
RE#
MI

FA
FA#
SOL
SOL#
LA
LA#
SI


DO....Si : it is one octave.
and any tones in octave have individual frequency
You can easily get it's frequencies from www.
there is special relation between 2 octave
and tones in one octave.
there fore you must first output these frq's
then write a code to generating frq's
if you connect a speaker to port 1 you can
hear good sounds without any driver.
also you can use 74ls07 for better waveform.
Best
Mehdi N.Rahni