client/pyscripts/theremin.py

   1 #!/usr/bin/python3
   2
   3 ### Parameters
   4 # Sound output parameters
   5 volume = 1.0
   6 sample_buf_size = 44
   7 sampling_freq = 44100 #Hz
   8
   9 # Frequency generator parameters
  10 min_freq = 200  #Hz
  11 max_freq = 2000 #Hz
  12
  13 # Proxmark3 parameters
  14 pm3_client="/usr/local/bin/proxmark3"
  15 pm3_reader_dev_file="/dev/ttyACM0"
  16 pm3_tune_cmd="hf tune"
  17
  18
  19 ### Modules
  20 import numpy
  21 import pyaudio
  22 from select import select
  23 from subprocess import Popen, DEVNULL, PIPE
  24
  25
  26 ### Main program
  27 p = pyaudio.PyAudio()
  28
  29 # For paFloat32 sample values must be in range [-1.0, 1.0]
  30 stream = p.open(format=pyaudio.paFloat32,
  31     channels=1,
  32     rate=sampling_freq,
  33     output=True)
  34
  35 # Initial voltage to frequency values
  36 min_v = 100.0
  37 max_v = 0.0
  38 v = 0
  39 out_freq = min_freq
  40
  41 # Spawn the Proxmark3 client
  42 pm3_proc = Popen([pm3_client, pm3_reader_dev_file, "-c", pm3_tune_cmd], bufsize=0, env={}, stdin=DEVNULL, stdout=PIPE, stderr=DEVNULL)
  43 mv_recbuf = ""
  44
  45 # Read voltages from the Proxmark3, generate the sine wave, output to soundcard
  46 sample_buf = [0.0 for x in range(0, sample_buf_size)]
  47 i = 0
  48 sinev = 0
  49 while True:
  50
  51   # Read Proxmark3 client's stdout and extract voltage values
  52   if(select([pm3_proc.stdout], [], [], 0)[0]):
  53
  54     b = pm3_proc.stdout.read(256).decode("ascii")
  55     if "Done" in b:
  56         break;
  57     for c in b:
  58       if c in "0123456789 mV":
  59         mv_recbuf += c
  60       else:
  61         mv_recbuf = ""
  62       if mv_recbuf[-3:] == " mV":
  63         v = int(mv_recbuf[:-3]) / 1000
  64         if v < min_v:
  65           min_v = v - 0.001
  66         if v > max_v:
  67           max_v = v
  68
  69         # Recalculate the audio frequency to generate
  70         out_freq = (max_freq - min_freq) * (max_v - v) / (max_v - min_v) \
  71         + min_freq
  72
  73   # Generate the samples and write them to the soundcard
  74   sinevs = out_freq / sampling_freq * numpy.pi * 2
  75   sample_buf[i] = sinev
  76   sinev += sinevs
  77   sinev = sinev if sinev < numpy.pi * 2 else sinev - numpy.pi * 2
  78   i = (i + 1) % sample_buf_size
  79   if not i:
  80     stream.write((numpy.sin(sample_buf) * volume).
  81         astype(numpy.float32).tobytes())