# Tone Ringer

from machine import Pin, PWM
from time import sleep

sequence  =  1  # 1  1  0  3  4 1
cadence   =  4  # 4  4  4  4  8 9
speed     =  9  # 7 20 16 16 32 6
frequency = round(455_000 / (14*2 * 3*4*5))

# GPIO pins on same PWM slice
pwm = [
    PWM(Pin(14), duty_u16=0x0000, invert=False),    #   0%
    PWM(Pin(15), duty_u16=0xffff, invert=True),     # 100% inverted
]

sequences = (
    (3, 4),
    (3, 4, 5),
    (4, 5),
    (5, 4),
    (8, 7),
)

cadences = (
    (1, 0),                 # continuous
    (1, 1),                 # SR
    (1, 2),                 # JP
    (1, 3),                 # BE
    (1, 4),                 # ITU
    (1, 5),                 # AT
    (1.25, 3.75),           # HU
    (1.5, 3.5),             # FR
    (2, 4),                 # US    
    (0.4, 0.2, 0.4, 2),     # UK
    (0.4, 0.2, 0.4, 3),     # HK
    (0.4, 0.2, 0.4, 4),     # SZ
)

c = cadences[cadence]
s = sequences[sequence]

while True:
    for j in range(0, len(c), 2):
        d = c[j] / speed
        pwm[0].duty_u16(0x8000)     # ≈50%
        pwm[1].duty_u16(0x8000)     # ≈50% inverted
        for i in range(speed):
            f = s[i % len(s)] * frequency
            pwm[0].freq(f)
            #pwm[1].freq(f)          # not necessary if pins on same slice
            sleep(d)
        pwm[0].duty_u16(0x0000)     #   0%
        pwm[1].duty_u16(0xffff)     # 100% inverted
        sleep(c[j+1])