Source code for pylibftdi.examples.midi_output

import time

from pylibftdi import Device


[docs]class MidiDevice(Device):
[docs]    def __init__(self, *o, **k):
        Device.__init__(self, *o, **k)
        self.baudrate = 31250


MAJOR_INTERVAL = [2, 2, 1, 2, 2, 2, 1, 2]
MINOR_INTERVAL = [2, 1, 2, 2, 1, 2, 2, 2]
START_NOTE = 48


[docs]def volume(beat):
    return 100 if beat % 2 else 127


[docs]def scale():
    midi = MidiDevice()

    note = START_NOTE
    for i in range(8):
        midi.write("\x90%c%c" % (chr(note), chr(volume(i))))
        time.sleep(0.25)
        midi.write("\x90%c\x00" % chr(note))
        note += MAJOR_INTERVAL[i]
        time.sleep(0.125)

    time.sleep(0.5)

    for i in range(8):
        note -= MINOR_INTERVAL[7 - i]
        midi.write("\x90%c%c" % (chr(note), chr(volume(i))))
        time.sleep(0.35)
        midi.write("\x90%c\x00" % chr(note))
        time.sleep(0.125)


if __name__ == "__main__":
    scale()