Interface and application programming

assignment
communicate, visualize &/or sonify the output of a sensor

I was playing with scratch and the lightsensor.

Result:
The Thinker
I made a movie where I let Harris play with the sensor. Hand on the sensor means high value, the monkey is small. Hand removed of the light sensor means low value and thus the monkey remains big. There is a flower falling down when pressing the down arrow key. The monkey starts to whistle 'twisted nerve' when the space key is pressed. And the brains of the thinker grow when the left arrow key is pressed.

Do not think too deeply about the significance of this work.

Findings
Scratch is not compatible with the light sensor ATtiny45 hello board of this week assignment. So, there was a need for an alternative communicating program to scratch. Therefore, the Neil's python script had to be changed to send data to scratch. Harris helped me out.
links:
http://academy.cba.mit.edu/labs/amsterdam/harris.sunyoto/input_devices/input_devices_with_scratch.zip
http://wiki.scratch.mit.edu/wiki/Communicating_to_Scratch_via_Actionscript

Neils version

changed program for scratch

#
# hello.light.45.py
#
# receive and display light level
# hello.light.45.py serial_port
#
# Neil Gershenfeld
# CBA MIT 10/24/09
#
# (c) Massachusetts Institute of Technology 2009
# Permission granted for experimental and personal use;
# license for commercial sale available from MIT
#

from Tkinter import *
import serial

WINDOW = 600 # window size
eps = 0.5 # filter time constant
filter = 0.0 # filtered value

def idle(parent,canvas):
   global filter, eps
   #
   # idle routine
   #
   byte2 = 0
   byte3 = 0
   byte4 = 0
   ser.flush()
   while 1:
      #
      # find framing
      #
      byte1 = byte2
      byte2 = byte3
      byte3 = byte4
      byte4 = ord(ser.read())
      if ((byte1 == 1) & (byte2 == 2) & (byte3 == 3) & (byte4 == 4)):
         break
   low = ord(ser.read())
   high = ord(ser.read())
   value = 256*high + low
   filter = (1-eps)*filter + eps*value
   x = int(.2*WINDOW + (.9-.2)*WINDOW*filter/1024.0)
   canvas.itemconfigure("text",text="%.1f"%filter)
   canvas.coords('rect1',.2*WINDOW,.05*WINDOW,x,.2*WINDOW)
   canvas.coords('rect2',x,.05*WINDOW,.9*WINDOW,.2*WINDOW)
   canvas.update()
   parent.after_idle(idle,parent,canvas)

#
# check command line arguments
#
if (len(sys.argv) != 2):
   print "command line: hello.light.45.py serial_port"
   sys.exit()
port = sys.argv[1]
#
# open serial port
#
ser = serial.Serial(port,9600)
ser.setDTR()
#
# set up GUI
#
root = Tk()
root.title('hello.light.45.py (q to exit)')
root.bind('q','exit')
canvas = Canvas(root, width=WINDOW, height=.25*WINDOW, background='white')
canvas.create_text(.1*WINDOW,.125*WINDOW,text=".33",font=("Helvetica", 24),tags="text",fill="#0000b0")
canvas.create_rectangle(.2*WINDOW,.05*WINDOW,.3*WINDOW,.2*WINDOW, tags='rect1', fill='#b00000')
canvas.create_rectangle(.3*WINDOW,.05*WINDOW,.9*WINDOW,.2*WINDOW, tags='rect2', fill='#0000b0')
canvas.pack()
#
# start idle loop
#
root.after(100,idle,root,canvas)
root.mainloop()

#
# hello.light.45.py
#
# receive and display light level
# hello.light.45.py serial_port
#
# Neil Gershenfeld
# CBA MIT 10/24/09
#
# (c) Massachusetts Institute of Technology 2009
# Permission granted for experimental and personal use;
# license for commercial sale available from MIT
#

from Tkinter import *
import serial, socket, array

WINDOW = 600 # window size
eps = 0.5 # filter time constant
filter = 0.0 # filtered value

def sendScratchCommand(cmd):
    host = 'localhost'
    port = 42001
    n = len(cmd)
    a = array.array('c')
    a.append(chr((n >> 24) & 0xFF))
    a.append(chr((n >> 16) & 0xFF))
    a.append(chr((n >> 8) & 0xFF))
    a.append(chr(n & 0xFF))
    scratchSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    scratchSock.connect((host,port))
    scratchSock.send(a.tostring() + cmd)
    scratchSock.close()

def idle(parent,canvas):
   global filter, eps
   #
   # idle routine
   #
   byte2 = 0
   byte3 = 0
   byte4 = 0
   ser.flush()
   while 1:
      #
      # find framing
      #
      byte1 = byte2
      byte2 = byte3
      byte3 = byte4
      byte4 = ord(ser.read())
      if ((byte1 == 1) & (byte2 == 2) & (byte3 == 3) & (byte4 == 4)):
         break
   low = ord(ser.read())
   high = ord(ser.read())
   value = 256*high + low
   filter = (1-eps)*filter + eps*value
   x = int(.2*WINDOW + (.9-.2)*WINDOW*filter/1024.0)
   canvas.itemconfigure("text",text="%.1f"%filter)
   canvas.coords('rect1',.2*WINDOW,.05*WINDOW,x,.2*WINDOW)
   canvas.coords('rect2',x,.05*WINDOW,.9*WINDOW,.2*WINDOW)
   canvas.update()
   parent.after_idle(idle,parent,canvas)
   sendScratchCommand('sensor-update "light"'+str(filter))

#
# check command line arguments
#
if (len(sys.argv) != 2):
   print "command line: hello.light.45.py serial_port"
   sys.exit()
port = sys.argv[1]
#
# open serial port
#
ser = serial.Serial(port,9600)
ser.setDTR()
#
# set up GUI
#
root = Tk()
root.title('hello.light.45.py (q to exit)')
root.bind('q','exit')
canvas = Canvas(root, width=WINDOW, height=.25*WINDOW, background='white')
canvas.create_text(.1*WINDOW,.125*WINDOW,text=".33",font=("Helvetica", 24),tags="text",fill="#0000b0")
canvas.create_rectangle(.2*WINDOW,.05*WINDOW,.3*WINDOW,.2*WINDOW, tags='rect1', fill='#b00000')
canvas.create_rectangle(.3*WINDOW,.05*WINDOW,.9*WINDOW,.2*WINDOW, tags='rect2', fill='#0000b0')
canvas.pack()
#
# start idle loop
#
root.after(100,idle,root,canvas)
root.mainloop()