midistepper/send.py

#!/usr/bin/env python3

import sys, argparse
import time
import threading

import mido
import serial

drum_channels = [9]

def serialreceive(ser):
  print("Serial running")
  while ser:
    try:
      line = ser.readline().decode()
      print(line)
    except Exception:
      pass


def main(argv):
  inputfile = ''
  outputport = ''
  parser = argparse.ArgumentParser()
  parser.add_argument('midifilename', help="the midi file you want to send. Set 'ALSA' for virtual midi port, see 'aconnect -o'")
  parser.add_argument('-P', '--serialport', help="serial port to open", default="/dev/ttyUSB0")
  parser.add_argument('--with-drums', action="store_true", help="send percussion track 10")
  parser.add_argument('--delay', help="add delay before startup", type=int, default=1)
  args = parser.parse_args()
  with serial.Serial(args.serialport, 115200, timeout=12) as ser:
    receivethread = threading.Thread(target=serialreceive, args=(ser,))
    receivethread.daemon = True
    receivethread.start()
    time.sleep(args.delay)
    if args.midifilename == 'ALSA':
#      portmidi = mido.Backend('mido.backends.portmidi')
      midi_in = mido.open_input()
    else:
      midi_in = mido.MidiFile(args.midifilename)
    with midi_in as mid:
      for msg in mid:
        time.sleep(msg.time)
        if not msg.is_meta:
          if msg.type == 'note_on' or msg.type == 'note_off' or msg.type == 'pitchwheel':
            if (not (msg.channel in drum_channels)) or args.with_drums:
              print(msg)
              ser.write(msg.bin())
            else:
              print("skipped percussion: " + str(msg))
          else:
            print("not sent: " + str(msg))
            if msg.type == 'program_change' and msg.program in [50,]:
              drum_channels.append(msg.channel)
              
        else:
          print("meta message: " + str(msg))
      print("EOF")
    print("done")
  print("serial closed")

if __name__ == "__main__":
  main(sys.argv[1:])