# # hello.mic.45.py # # plot microphone audio # hello.mic.45.py serial_port # # Neil Gershenfeld 4/1/14 # (c) Massachusetts Institute of Technology 2014 # # This work may be reproduced, modified, distributed, # performed, and displayed for any purpose. Copyright is # retained and must be preserved. The work is provided # as is; no warranty is provided, and users accept all # liability. # from tkinter import * import serial NX = 500 NY = 500 nloop = 100 path = [] baseline = 0 baseline_filt = 0.01 gain = .2 def idle(parent,canvas): global path, baseline # # idle routine # # look for framing # byte2 = 0 byte3 = 0 byte4 = 0 while 1: byte1 = byte2 byte2 = byte3 byte3 = byte4 byte4 = ord(ser.read()) if ((byte1 == 1) & (byte2 == 2) & (byte3 == 3) & (byte4 == 4)): break path = [] for i in range(nloop): lo = ord(ser.read()) hi = ord(ser.read()) if (hi < 2): reading = 512 + 256*hi + lo else: reading = 256*hi + lo - 512 baseline = baseline_filt*reading + (1-baseline_filt)*baseline value = NY/2 + gain*(reading - baseline) path.append(i*NY/float(nloop)) path.append(value) canvas.delete("path") canvas.create_line(path,tag="path",width=3,fill="#00b000") parent.after_idle(idle,parent,canvas) # # check command line arguments # if (len(sys.argv) != 2): print("command line: hello.mic.45.py serial_port") sys.exit() port = sys.argv[1] # # open serial port # ser = serial.Serial(port,9600) # # start plotting # root = Tk() root.title('hello.mic.45.py') root.bind('q','exit') canvas = Canvas(root, width=NX, height=NY, background='white') canvas.pack() root.after(100,idle,root,canvas) root.mainloop()