SSTC USB interrupter based on Raspberry Pi Pico

[AdamRozdrazewski]

Hello

Lately i build simple USB interrupter on Pi pico and want to share my code and ask for help. Its quite messy but works.
There is no ontime regulation. To achieve polyphonic ive been using IC OR gate to add up signals(don't know how to code it). Im asking for advice how to add these featuers and make interrupter safe for drsstc. Its based on circuitpython midi library

Code: [Select]

import random
import time
import pwmio
import usb_midi
import board
import adafruit_midi
from adafruit_midi.control_change import ControlChange
from adafruit_midi.note_off import NoteOff
from adafruit_midi.note_on import NoteOn
from adafruit_midi.pitch_bend import PitchBend
from analogio import AnalogIn



# GLOBAL VARIABLES
freq = 100
current_duty_cycle2 = 0
notes_table = []
notes_state = [0] * 128
latest_on_tmp = 0
last_position1 = 0
last_position2 = 0
playing = True


analog_in1 = AnalogIn(board.A1)
analog_in2 = AnalogIn(board.A2)
analog_in3 = AnalogIn(board.A0)

factor1 = 1
frequency1 = 100
factor2 = 1
frequency2 = 100

pwm3 = pwmio.PWMOut(board.GP13, duty_cycle=0, frequency=100, variable_frequency=True)
pwm4 = pwmio.PWMOut(board.GP9, duty_cycle=0, frequency=100, variable_frequency=True)
print(usb_midi.ports)
midi = adafruit_midi.MIDI(
    midi_in=usb_midi.ports[0], in_channel=(0,1,2,3), midi_out=usb_midi.ports[1], out_channel=0
)
print("Midi test")
print("Default output channel:", midi.out_channel + 1)
print("Listening on input channel:", midi.in_channel[0] + 1, " and ", midi.in_channel[0] + 1)

def note_to_herz(control):
    return int(notes_table[control])

def create_table():
    a = 440.0
    for x in range(0,127):
       notes_table.append((a / 32.0) * (2.0 ** ((x - 9) / 12.0)))
create_table()
while True:

      time.sleep(0.0005)
      dc1 = int(analog_in1.value / 3) #reading values from potentiometers range is from 0 to 65535
      dc2 = int(analog_in2.value / 3) #max 33% duty cycle
     

      if dc1 <= 300:    ## fixing ADC's 0
          dc1 = 0
      if dc2 <= 300:
          dc2 = 0
       
     

      msg = midi.receive()
      if msg is not None:
          print("Received:", msg, "at", time.monotonic())
          if msg.channel == 0:  ## channel 1
              if (isinstance(msg, PitchBend)):
                  pitch = msg.pitch_bend
                  factor1 = 2**((pitch - 8192) / 8192)
                  pwm3.frequency = int(frequency1 * factor1)
                  pwm3.duty_cycle = dc1
                  playing = True
                  print("PITCH: ", pitch, "PITCH: ", factor1)
              elif (isinstance(msg, NoteOn)):
                  notes_state[msg.note] = 1
                  latest_on_tmp = time.monotonic()
                  pwm3.frequency = int(float(note_to_herz(msg.note) * factor1))
                  frequency1 = pwm3.frequency
                  pwm3.duty_cycle = dc1
                  playing = True
                  print("[CH1] NOTE ", msg.note, " ON with FREQ: ", str(pwm3.frequency), "Hz at", time.monotonic())
              elif (isinstance(msg, NoteOff)):
                  notes_state[msg.note] = 0
                  pwm3.duty_cycle = 0
                  print("NOTE ", msg.note, " OFF AT CHANNEL ", msg.channel, " with FREQ: ", str(note_to_herz(msg.note)), "Hz at", time.monotonic())
          elif msg.channel == 1:  ## channel 2
              if (isinstance(msg, PitchBend)):
                  pitch = msg.pitch_bend
                  factor2 = 2**((pitch - 8192) / 8192)
                  pwm4.frequency = int(frequency2 * factor2)
                  pwm4.duty_cycle = dc2
                  playing = True
                  print("PITCH: ", pitch, "PITCH: ", factor2)
              elif (isinstance(msg, NoteOn)):
                  notes_state[msg.note] = 1
                  latest_on_tmp = time.monotonic()
                  pwm4.frequency = int(float(note_to_herz(msg.note) * factor2))
                  frequency2 = pwm4.frequency
                  pwm4.duty_cycle = dc2
                  playing = True
                  print("[CH2] NOTE ", msg.note, " ON with FREQ: ", str(pwm4.frequency), "Hz at", time.monotonic())
              elif (isinstance(msg, NoteOff)):
                  notes_state[msg.note] = 0
                  pwm4.duty_cycle = 0
                  print("NOTE ", msg.note, " OFF AT CHANNEL ", msg.channel, " with FREQ: ", str(note_to_herz(msg.note)), "Hz at", time.monotonic())
      if ((latest_on_tmp + 0.5) < time.monotonic()) and playing:  ## fixing bug when stoping music from midi program
          for note in notes_state:
            notes_state[note] = 0
          pwm3.duty_cycle = 0
          pwm4.duty_cycle = 0
          playing = False
          print("[TIMEOUT] OFF with all FREQs at", time.monotonic())