from machine import Pin, PWM
import time
_init()

tempo = 2

tones = {
    'c': 262,
    'd': 294,
    'e': 330,
    'f': 349,
    'g': 392,
    'a': 440,
    'b': 494,
    'C': 523
}

speaker = PWM(Pin(15, Pin.OUT))

melody = 'abcdefgC'
rhythm = [8, 2, 1, 8, 3, 4, 6, 8]

for tone, length in zip(melody, rhythm):
    speaker.duty(512)
    speaker.freq(tones[tone])
    time.sleep(tempo/length)
    speaker.duty(0)
    time.sleep(tempo/length/4)