Sound and music

Crash-tan’s Tip: Browsers keep a page quiet until you’ve clicked on it. Press Try it or Run and I’m allowed to make noise.

Beeps and tones

BEEP is the classic. SOUND plays a tone: how high, in hertz, and for how many seconds.

SCREEN 320, 240
BEEP
SOUND 440, 0.2
SOUND 660, 0.2
SOUND 880, 0.4
PRINT "ta-da!"
PAUSE

ta-da!

When a program ends, its sounds stop with it, so PAUSE at the end keeps it going until you press a key. A game never needs one: it’s still running.

Tunes

PLAY plays a tune written as notes, the way the old BASICs did it: T sets the tempo, O the octave, L how long a note is (4 is a quarter note, 8 an eighth), and then the notes themselves.

SCREEN 320, 240
PLAY "T160 O4 L8 C D E F G4 G4 A A A A G2"
PRINT "done"
PAUSE

done

PLAY waits for its tune to finish. In a game you’d rather it didn’t, so the game goes on while it plays: !! background.

SCREEN 320, 240
PLAY "T120 O3 L4 C E G > C < G E C2" !! background
x = 0
DO
    IF COOLDOWN(1)
        MEMORYBUFFER "scene"
            CIRCLE (x, 120), 10, 13, 13
        END MEMORYBUFFER
        FRAME
            CLS
            PUTIMAGE (0, 0), "scene"
        END FRAME
        x = (x + 3) MOD 320
    END IF
LOOP

Music

For a whole song with several instruments, describe it in a MUSIC block: the patterns, the tracks in each one, and the order they play in. Then PLAYMUSIC plays it, in the background, for as long as you like.

SCREEN 320, 240
MUSIC "theme"
    TEMPO 140
    PATTERN "verse"
        TRACK !! channel(1) notes("o4 l8 c e g e c e g e")
        TRACK !! channel(2) notes("o2 l2 c g")
    END PATTERN
    PATTERN "chorus"
        TRACK !! channel(1) notes("o4 l8 f a > c < a g b > d < b")
        TRACK !! channel(2) notes("o2 l2 f g")
    END PATTERN
    ARRANGEMENT
        PLAY "verse" !! repeat(2)
        PLAY "chorus"
    END ARRANGEMENT
END MUSIC
PLAYMUSIC "theme"
PRINT "playing", musicplaying()
PAUSE

There’s a lot more where that came from: instruments you design yourself, envelopes and filters, samples, fading one song into another. The reference has every word, and the music lessons will come later in this book.