add theremin.py script, (@rosco)

client/pyscripts/theremin.py

@@ -0,0 +1,78 @@
+#!/usr/bin/python3
+
+### Parameters
+# Sound output parameters
+volume = 1.0
+sample_buf_size = 44
+sampling_freq = 44100 #Hz
+
+# Frequency generator parameters
+min_freq = 200  #Hz
+max_freq = 2000 #Hz
+
+# Proxmark3 parameters
+pm3_client="/usr/local/bin/proxmark3"
+pm3_reader_dev_file="/dev/ttyACM0"
+pm3_tune_cmd="hf tune"
+
+
+### Modules
+import numpy
+import pyaudio
+from select import select
+from subprocess import Popen, DEVNULL, PIPE
+
+
+### Main program
+p = pyaudio.PyAudio()
+
+# For paFloat32 sample values must be in range [-1.0, 1.0]
+stream = p.open(format=pyaudio.paFloat32,
+		channels=1,
+		rate=sampling_freq,
+		output=True)
+
+# Initial voltage to frequency values
+min_v = 100.0
+max_v = 0.0
+v = 0
+out_freq = min_freq
+
+# Spawn the Proxmark3 client 
+pm3_proc = Popen([pm3_client, pm3_reader_dev_file, "-c", pm3_tune_cmd],
+		bufsize=0, env={}, stdin=DEVNULL, stdout=PIPE, stderr=DEVNULL)
+mv_recbuf = ""
+
+# Read voltages from the Proxmark3, generate the sine wave, output to soundcard
+sample_buf = [0.0 for x in range(0, sample_buf_size)]
+i = 0
+sinev = 0
+while True:
+
+  # Read Proxmark3 client's stdout and extract voltage values
+  if(select([pm3_proc.stdout], [], [], 0)[0]):
+
+    b = pm3_proc.stdout.read(256).decode("ascii")
+    for c in b:
+      if c in "0123456789 mV":
+        mv_recbuf += c
+      else:
+        mv_recbuf = ""
+      if mv_recbuf[-3:] == " mV":
+        v = int(mv_recbuf[:-3]) / 1000
+        if v < min_v:
+          min_v = v - 0.001
+        if v > max_v:
+          max_v = v
+
+        # Recalculate the audio frequency to generate
+        out_freq = (max_freq - min_freq) * (max_v - v) / (max_v - min_v) + min_freq
+
+  # Generate the samples and write them to the soundcard
+  sinevs = out_freq / sampling_freq * numpy.pi * 2
+  sample_buf[i] = sinev
+  sinev += sinevs
+  sinev = sinev if sinev < numpy.pi * 2 else sinev - numpy.pi * 2
+  i = (i + 1) % sample_buf_size
+  if not i:
+    stream.write((numpy.sin(sample_buf) * volume).astype(numpy.float32).tobytes())