1 is the shortest note and 9 the longest.
They are related to musical convention
according to the following table.
Number | Note Name | Musical symbol |
1 | semi quaver | |
2 | dotted semi-quaver | |
3 | quaver | |
4 | dotted quaver | |
5 | crotchet | |
6 | dotted crotchet | |
7 | minim | |
8 | dotted minim | |
9 | semi-breve | |
Each of these controls the length of all
notes which follow it until you give a new
number code.
You can also use the numbers from 10 to
12 to specify triplet notes (three notes
played in the time normally used for two).
Number | Note Name | Musical symbol |
10 | triplet semi-quaver | |
11 | triplet quaver | |
12 | triplet crotchet | |
Each of these only applies to the three
notes following it and must be followed by
their three names, eg
10 LET a$="11ACE"
A rest (no note playing) is specified by a &
and has the same length as the current
note. For example
10 LET a$="7A&B&C&D&E"
is five minims with equal pauses between
them.
Tied notes can be indicated by giving the
two note durations connected by an
underscore character and the note name, eg
10 LET a$="3_5A"
The second note duration you give will also
apply to any following codes until you give
another duration code.
The N Command |
In some or the examples you will see the
letter N used to introduce a series of
notes within the string, eg |
LET a$="O7N1CDE" |
N is used in cases where two sets of
numbers would otherwise clash. In the
example above, 0 is set to octave 7, then
a series of notes is given, starting with
the duration code 1.
Without the N code, the Spectrum 128
would read the octave code as 71 -
obviously not what was intended! |
Note volume
The overall volume of the sound is
controlled by the volume setting of your
TV or amplifier. You can control the
volume of individual notes and phrases
within the tune by using the V command.
V followed by a number from 0 to 15 sets
the following note(s) to a constant volume.
The lower the number, the quieter the
sound, with V0 completely silent (V0 is a
useful way of stopping one channel playing
while others continue). V15 is the
maximum and is used automatically by the
Spectrum 128 if you do not specify a level.
The low volumes are very quiet and you
will normally use 10 to 15 unless you are
outputting to an amplification system or
via the MIDI port to a synthesizer. Try
running this program
10 LET a$="V10cdefgabCDEFGAB"
20 PLAY a$
Now try changing the number after the V
to a new value to hear the difference
Volume effects
Instead of you just setting each note to a
fixed volume, PLAY also lets you change
the volume of the sound while it is playing.
For example, you can make a note start
suddenly and then die away (like a piano)
or make a sound effect rise and fall in
volume (like a steam train).
This effect is controlled by the letter W
which can be included in any of the strings
controlled by the PLAY command. You
must also include the letter U in each string
where you want to use the effect. You
cannot use it if the string already has a
volume setting (if it contains a V) - the
volume command will overrule the effect.
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