Threaded Arduino Reader / Plotter / Writer

arduinoPlotter.py

'''
I adapted the live plotting code from somewhere but I cannot remember where.
If you know where, I would be happy to add it to the comment here.
'''
'''
I adapted the live plotting code from somewhere but I cannot remember where.
If you know where, I would be happy to add it to the comment here.
'''

import threading
import time
import gobject
import matplotlib
matplotlib.use('GTKAgg')
import matplotlib.pyplot as plt
import serial
import Queue
import datetime
import random

class Arduino(threading.Thread):
    def __init__(self, queue, timeout):
        threading.Thread.__init__(self)
        self.ser = serial.Serial("/dev/ttyUSB0", 115200)
        self.queue = queue
        self.writeData = True
        self.timeout = timeout
        self.timer = time.time()
        print 'initiated arduino'
		
    def run(self):
        while True:
            if time.time() - self.timer > self.timeout:
                self.ser.write('t')
                self.timer = time.time()
                
            if self.ser.inWaiting() > 0:
                reading = ''
                while '\r\n' not in reading:
                    reading += self.ser.read()
                #print 'Data from Arduino: ', reading
                reading.split('\r\n')[0]
                newData = int(reading)
                newData = random.randint(0, 255)
                self.queue.put(newData)
                if self.writeData:
                    writeData(newData)
                    
def update():
    global q
    if not q.empty():
        newData = q.get()
        data.pop(0)
        data.append(newData)
    f.clear()
    f.suptitle("Temperature")
    a = f.add_subplot(111)
    x, = a.plot(range(winLength), data, 'b-')
    a.grid(True)
    plt.xlabel("Time")
    plt.ylabel("Temperature")
    minY = min(data)
    maxY = max(data)
    a.axis([0, winLength, minY-0.3, maxY+0.3])
    f.canvas.draw_idle()
    return True

def writeData(data):
    fileName = str(datetime.date.today())+'.log'
    with open(fileName, 'ab') as f:
	    f.write(str(data))
	    f.write('\n')

if __name__ == '__main__':
    q = Queue.Queue()
    timeout = 1 # second
    print 'Starting Arduino'
    ard = Arduino(q, timeout)
    ard.start()
    
    f = plt.figure()
    winLength = 25
    
    data = [0 for _ in range(winLength)]
    gobject.timeout_add(timeout*1000, update)    
    plt.show()