1. Music

See: https://microbit-micropython.readthedocs.io/en/stable/music.html

Warning

For use of the inbuilt speaker on the V2 microbit, set the speaker to on.

For use of an external buzzer on a breadboard, set the speaker to off so that the in-built speaker does not also play sounds.

1.1. Speaker V2

By default sound output will be via both pin0 and the V2 built-in speaker.
The V2 built-in speaker can be turned off or on without affecting playing via pin0.
When flashing a new script to the microbit, the V2 built-in speaker will be on, unless the code sets it to off.

speaker.off(): Use speaker.off() to turn off the speaker. This does not disable sound output to pin0.

speaker.on(): Use speaker.on() to turn on the speaker.

1.2. Music Library

Put import music at the top under from microbit import *.

from microbit import *
import music

1.3. Play notes

music.play(notes, pin=pin0, wait=True, loop=False): Play the notes.

Notes can be a string, such as ‘c1:4’, or a list of notes as strings, such as [‘c’, ‘d’, ‘e’]

The duration and octave values are reset to their defaults (of 4 each) before the music is played.

Octaves start on the note “C”.

The output pin can be used to override the default pin0. pin=None prevents sounds from being played.

If wait is set to True, playing is blocking, and the music will be played to the end.

If loop is set to True, the music repeats until stop is called. Set wait to False to use this.

Use music.play(note) to play a note given by the note variable.
The note is written as a string with quotes: ‘c4:8’.
This is a c note in octave 4 with a duration of 8 ticks (a minim or 2 crotchet beats).

from microbit import *
import music

note = 'c4:8'
music.play(note)

Use music.play(notes_list) to play a list of notes in the notes_list variable.
The code below plays a list of notes. The octave changes from 4 to 5.
Octaves start on the note “C”.

from microbit import *
import music

notes_list = ['e4', 'f#', 'g', 'a', 'b', 'c5', 'd', 'e']
music.play(notes_list)

Tasks

Play the note e over and over again with 1 second between them.
Play the notes c, e, g over and over again with 1 second between replays.

1.4. Notes

An individual note is specified as: NOTE[octave][:duration].

Notes are the letters a to g with or without an accidental (# for a sharp, b for a flat).
Lower case or upper case notes are the same. eg. A and a are the same.
Ab is A-flat and C# is C-sharp.
Use r or R for a rest (silence).

If the octave is left out it defaults to 4 (containing middle C).
Octaves start on the note “C”.
If the duration is left out it defaults to 4 (a crotchet).
For example, a5:4 refers to the note “A” in octave 5 that lasts for four ticks (4 ticks is usually a crotchet beat).

The octave and duration parameters are states that carry over to subsequent notes until re-specified.

e.g. [‘c4:1’, ‘e’, ‘g5:8’] The e is octave 4 for 1 tick. The g is octave 5 for 8 ticks.

Tasks

Play the 5 notes: c, e, g, e, c in octave 4.
Starting with C in octave 4, play the next 6 notes that are each one semitone higher than the previous note. Use sharps as needed.
Starting with G flat in octave 5, play the next 6 notes that are each one semitone lower than the previous note. Use flats as needed.

1.5. Tempo

music.set_tempo(ticks=4, bpm=120): Sets the tempo for playback.

The number of ticks, expressed as an integer, make a beat. The default is 4 ticks per beat.

Each beat is to be played at a certain rate, beats per minute, expressed as an integer. The default is 120 bpm.

Examples of use:
music.set_tempo() - reset the tempo to default of ticks = 4, bpm = 120
music.set_tempo(ticks=8) - change the beat to 8 ticks
music.set_tempo(bpm=240) - just change the tempo to 240 beats per minute

The length of a beat in milliseconds is (60 sec * 1000 / bpm).

For the default value of 120 bpm, that’s 60000/120 or 1 beat in 500 milliseconds, which is 2 beats per second.

The code below plays a list of notes.

The tempo can be sped up by changing ticks from 4 to 8 or by changing bpm from 120 to 240.

from microbit import *
import music

notes_list = ['e4', 'f#', 'g', 'a', 'b', 'c5', 'd', 'e']

music.set_tempo(ticks=4, bpm=120)
music.play(notes_list)
music.set_tempo(ticks=8, bpm=120)
music.play(notes_list)
music.set_tempo(ticks=8, bpm=240)
music.play(notes_list)

music.get_tempo(): Gets the current tempo as a tuple of integers: (bpm, ticks).

To display the tuple from get_tempo it can be converted to a string:

from microbit import *
import music

music.set_tempo(ticks=4, bpm=240)
tempo_data = str(music.get_tempo())
display.scroll(tempo_data)
# (240, 4)

Each value in the tuple can be accessed using its index as shown below:

from microbit import *
import music

music.set_tempo(ticks=2, bpm=120)
tempo_data = music.get_tempo()
bpm = tempo_data[0]
ticks = tempo_data[1]
display.scroll(bpm)
display.scroll(ticks)

For advanced users, tuple unpacking can be used instead of indices: bpm, ticks = music.get_tempo().

See: https://www.w3schools.com/python/python_tuples_unpack.asp

from microbit import *
import music

music.set_tempo(ticks=2, bpm=120)
bpm, ticks = music.get_tempo()
display.scroll(bpm)
display.scroll(ticks)

Tasks

Play the 5 notes: c, e, g, e, c with a tempo of 120, 180 and 240bpm without a for-loop.
Play the 3 notes: ‘e4:4’, ‘f#’, ‘g’ with a tempo of 120, 180 and 240bpm using a for-loop for the tempos.
Design a function that takes the list of 3 notes [‘e4:4’, ‘f#’, ‘g’] as one parameter; takes a tempo list of 120, 240, 360 , 480 and 600 bpm as a second parameter and a third parameter sleep_time with default value 1000. Use a repeat loop to set the tempo and play the notes_list.

1.6. Volume V2

music.set_volume(volume): Configure the output volume of the microbit speaker and pins.

volume is an integer between 0 and 255.

The code below sets the volume at different levels and plays a C note in octave 4 for 2 ticks at each volume.

from microbit import *
import music


note = "c4:2"
while True:
    set_volume(255)
    music.play(note)
    set_volume(128)
    music.play(note)
    set_volume(64)
    music.play(note)

Tasks

Instead of playing the same note each time, play a different note “c4:2”, “e4:2”, “f#4:2” at a different volume.
Put the 3 sound levels in a list and use a for-loop to set the volume and play the note “c4:2”.
To the previous task, add the ability to stop the playing by exiting the while True loop on pressing the A-button via the use of break. Pressing the reset button on the back of the microbit will restart the code.

1.7. Stop background music

music.stop(pin=pin0): Stops all music playback on the built-in speaker and any pin outputting sound.

An optional argument can be provided to specify a pin, eg. music.stop(pin=pin1).

In the example below wait=False so that the music plays in the background.
In the example below loop=True so that the music loops forever.
“A” is scrolled in the background to suggest pressing A to stop the music.

from microbit import *
import music

# Define the melody
melody1 = ['C4:4', 'C4:4', 'G4:4', 'G4:4',
            'A4:4', 'A4:4', 'G4:8',
            'F4:4', 'F4:4', 'E4:4', 'E4:4',
            'D4:4', 'D4:4', 'C4:8']

# Play the melody
music.play(melody1, wait=False, loop=True)

display.scroll("A", wait=False, loop=True)
while True:
    # Allow 2 seconds to choose to press the A-button
    sleep(2000)
    if button_a.was_pressed():
        # Stop the melody
        music.stop()
        # exit the while loop
        break

display.scroll("THE END")

Tasks

Add a rest equivalent to 4 crotchets to the end of the melody above so it provides a pause equivalent to one bar as the melody loops.
Modify the example above to have 2 melodies: melody1 = [‘E4:4’, ‘D:4’, ‘C:4’, ‘D:4’, ‘E:4’, ‘E:4’, ‘E:8’, ‘D:4’, ‘D:4’, ‘D:8’, ‘E:4’, ‘G:4’, ‘G:8’] and melody2 = [‘E4:4’, ‘D:4’, ‘C:4’, ‘D:4’, ‘E:4’, ‘E:4’, ‘E:4’, ‘E:4’, ‘D:4’, ‘D:4’, ‘E:4’, ‘D:4’, ‘C:16’]. Firstly, melody1 loops and can be stopped by the A-button. Then melody2 loops and can be stopped by the B-button.

1.8. Reset music

music.reset(): Resets the state of the following attributes as listed:

ticks = 4; bpm = 120; duration = 4; octave = 4

1.9. Custom tunes

Make use of these custom dictionaries that store notes and tempos for some short tunes.

The notes are a string with a space as a separator. Use the split method to convert the string to a list of notes. See: https://www.w3schools.com/python/ref_string_split.asp

from microbit import *
import music

scale = {"name": "Scale", "notes": "C5 B A G F E D C", "tempo": 120}
reverse = {"name": "Reverse", "notes": "C D E F G A B C5", "tempo": 120}
mystery = {"name": "Mystery", "notes": "E B C5 A B G A F", "tempo": 120}
gilroy = {"name": "Gilroy", "notes": "A F E F D G E F", "tempo": 120}
falling = {"name": "Falling", "notes": "C5 A B G A F G E", "tempo": 120}
hopeful = {"name": "Hopeful", "notes": "G B A G C5 B A B", "tempo": 120}
tokyo = {"name": "Tokyo", "notes": "B A G A G F A C5", "tempo": 120}
paris = {"name": "Paris", "notes": "G F G A - F E D", "tempo": 120}
rising = {"name": "Rising", "notes": "E D G F B A C5 B", "tempo": 120}
sitka = {"name": "Sitka", "notes": "C5 G B A F A C5 B", "tempo": 120}

Challenge

Play each of the custom dictionaries notes.