W11 - Interface and Application Programming

Assignments:

• Write an application that interfaces a user with an input and/or output device.
• Compare as many tool options as possible.

Board

I decided to make a quick interface to visualize the data coming from one of my temperature sensor boards. I decided to base my interface on python due to the fact that I will be using python for further developing my interface for my final project. I based my weekly assignment on matpllot lib and made a real time temperarure plot. I decided to connect one of my sensor nodes with RF capabilities to my USB terminal. The node communicates with an external RF node, and sends the temperature data to my computer through pyserial.

REading Serial -> Saving Data into CSV file -> Using PyPlot Lib to create a real time plot.

    

      import serial
      import time
      import csv
      import matplotlib
      matplotlib.use("tkAgg")
      import matplotlib.pyplot as plt
      import numpy as np

      def get_temp(temp_string):
          return float(temp_string[9:15])

      ser = serial.Serial('/dev/tty.usbserial-AR0K4YH6')
      ser.baudrate = 115200
      ser.flushInput()

      available_temp_nodes = []
      available_light_nodes = []
      received_temp = []
      received_light = []

      plot_window = 20
      y_var = np.array(np.zeros([plot_window]))

      plt.ion()
      fig, ax = plt.subplots()
      line, = ax.plot(y_var)


      while True:

          try:
              ser_bytes = ser.readline()
              ser_string = str(ser_bytes)
              #print(ser_string)
          except:
              print("No Serial Available")

          #Create network.
          if ser_string[4] == 'L':
              #Check if node is new
              if not (int(ser_string[7]) in available_light_nodes):
                  print('New Light Node Has Connected! =) ')
                  print('Adding Node', ser_string[2:8], 'To Network...')
                  available_light_nodes.append(int(ser_string[7]))
                  print('Node has been added! =) ')

          if ser_string[4] == 'T':
              #print(get_temp(ser_string))
              with open("test_data.csv","a") as f:
                  writer = csv.writer(f,delimiter=",")
                  writer.writerow([time.time(),get_temp(ser_string)])

              plt.style.use('dark_background')
              y_var = np.append(y_var,get_temp(ser_string))
              y_var = y_var[1:plot_window+1]
              line.set_ydata(y_var)
              ax.relim()
              ax.autoscale_view()
              fig.canvas.draw()
              fig.canvas.flush_events()

              if not (int(ser_string[7]) in available_light_nodes):
                  print('New Temperature Node Has Connected! =) ')
                  print('Adding Node', ser_string[2:8], 'To Network...')
                  available_light_nodes.append(int(ser_string[7]))
                  print('Node has been added! =) ')

    
  

And here is my Demo! Click to start video.