Commodore 128 System Manual page 153

So far, your PLAY statements only played whole notes. Add notes
of different duration by placing duration control characters in your
PLAY string as follows:
70 PLAY " MV2O6T0U7X0HCDQEFIGASB"
Line 70 PLAYs voice 2 in octave 6 at volume level 7 with the
redefined piano envelope (0) on and filter turned off. This
statement PLAYs the notes C and D as half notes, E and F as
quarter notes, G and A as eighth notes and B as a sixteenth note.
Notice the difference between the piano envelope in line 40 and
the redefined piano envelope in line 70. Line 40 actually sounds
more like a piano than line 70.
You can PLAY sharp, flat and dotted notes by preceding the
notes within quotes with the following characters:
# — Sharp
$ - Flat
. — Dotted
A dotted note plays one-and-a-half times longer than a note that
is not dotted.
Now try adding sharp, flat and dotted notes with this statement:
80 PLAY " MV1O4T4U8X0.HCDQ#EFI$GA.S#B"
Line 80 PLAYS voice 1 in octave 4 at volume level 8 with the flute
envelope turned on and the filter turned off. It also PLAYS C and
D as dotted half notes, E and F as sharp quarter notes, G and A
as flat eighth notes and B as a sharp dotted sixteenth note. You
can add rests (R) at any place within your PLAY string.
Up until now your statement examples have left the filter off within
the sound synthesizer and have not realized the true power
behind it. Now that you have digested most of the sound and
music statements and the SID control characters, move on to the
next section to learn how to enhance your musical quality with
the FILTER statement.
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