#
# hello3.step.py
# receive and plot step response
# Neil Gershenfeld CBA MIT
# 10/29/05
#
from Tkinter import *
import serial

WINDOW = 600
NSAMPLES = 254
MAX = 1040
eps = .9
saveflag = 0
index = 0
path = []
step = []
path_filt = []
step_filt = []
baseline = []

def idle(parent,canvas):
   global index, channel, baseline, path, path_filt, step, step_filt, saveflag
   #
   # idle routine
   #
   #eps = float(sfilter.get())
   
   lowbits = ord(ser.read())
   hibits = ord(ser.read())

   one = ord(ser.read())
   two = ord(ser.read())
   three = ord(ser.read())
   four = ord(ser.read())

   while 1:
      one = two
      two = three 
      three = four 
      four = ord(ser.read())
      if ((one == 1) & (two == 2) & (three == 3) & (four == 4)):
         print "got framing @#"
 	 break




   print "one two three four:", one, ",", two, ",", three, ",", four
   print "low:", lowbits, " hibits:", hibits 
   voltage = 256*hibits + lowbits
   print "voltage A/D: " , voltage
   
   voltage = float(voltage/1023.0)   
   voltage = voltage * 5.0   
   print "Voltage Real: ", voltage

   canvas.itemconfigure("y0",text="Input Voltage is: %.2f"%voltage)
   

   lo_dn = 0
   hi_dn = 0
   lo_up = 0
   hi_up = 0  
 
   if ((lo_dn == 1) & (hi_dn == 2) & (lo_up == 3) & (hi_up == 4)):
      if (path_filt == []):
         path_filt = path
	 step_filt = step
      else:
         for i in range(len(path_filt)):
	    path_filt[i] = (1-eps)*path_filt[i] + eps*path[i]
         for i in range(len(step_filt)):
	    step_filt[i] = (1-eps)*step_filt[i] + eps*step[i]
      canvas.delete("path")
      canvas.create_line(path_filt,tag="path",width=3,fill="#00b000")
      if (baseline != []):
         canvas.delete("baseline_path")
         canvas.create_line(baseline,tag="baseline_path",width=3,fill="#b00000")
   
      print "popo"

      canvas.itemconfigure("y0",text="y[0]: %.2f"%step_filt[0])
      canvas.itemconfigure("y1",text="y[1]: %.2f"%step_filt[1])
      canvas.itemconfigure("y-1",text="y[-1]: %.2f"%step_filt[-1])
      canvas.coords('x0',0,.95*WINDOW,step_filt[0],WINDOW)
      
      
      
      if (saveflag == 1):
         file = open(soutfile.get(),"w")
	 for i in range(len(step_filt)):
	    file.write("%f\n"%(step_filt[i]))
	 file.close()
	 print 'saved to '+soutfile.get()
         saveflag = 0
      index = 0
      path = []
      step = []
   else:
      value_up = 256*hi_up + lo_up
      value_dn = 256*hi_dn + lo_dn
      value = (value_up + (1023-value_dn))/2.0
      index += 2
      step.insert(0,value)
      path.insert(0,WINDOW-value*WINDOW/float(MAX))
      path.insert(0,WINDOW-index*WINDOW/float(NSAMPLES))
   parent.after_idle(idle,parent,canvas)

def save_data(parent):
   global saveflag
   saveflag = 1

def store_baseline(parent):
   global path_filt, baseline
   baseline = []
   for i in range(len(path_filt)):
      baseline.append(path_filt[i])

#
# open serial port
#
#ser = serial.Serial('/dev/ttyUSB0',9600)
ser = serial.Serial('/dev/ttyS0',9600)
#ser = serial.Serial('COM6',9600)
ser.setDTR()
#
# find framing
#
print "finding 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)):
      print "start plotting"
      break
#
# start plotting
#
root = Tk()
root.title('hello3.step.py')
root.bind('q','exit')

canvas = Canvas(root, width=WINDOW, height=.2*WINDOW, background='yellow')
canvas.create_text(.5*WINDOW,.1*WINDOW,font=("Helvetica", 24),tags="y0",fill="#0000b0")

#canvas.create_text(.5*WINDOW,.9*WINDOW,font=("Helvetica", 24),tags="y1",fill="#0000b0")
#canvas.create_text(.8*WINDOW,.9*WINDOW,font=("Helvetica", 24),tags="y-1",fill="#0000b0")
#canvas.create_rectangle(0,.95*WINDOW,0,WINDOW, tags='x0', fill='#b00000')
canvas.pack()

ioframe = Frame(root)
#Label(ioframe, text=" filter (0-1):").pack(side="left")
#sfilter = StringVar()
#sfilter.set(str(eps))
#Entry(ioframe, width=5, textvariable=sfilter).pack(side="left")
#Label(ioframe, text=" ").pack(side="left")
#basebtn = Button(ioframe, text="store baseline")
#basebtn.bind('<Button-1>',store_baseline)
#basebtn.pack(side="left")
#Label(ioframe, text=" ").pack(side="left")
#savebtn = Button(ioframe, text="save data")
#savebtn.bind('<Button-1>',save_data)
#savebtn.pack(side="left")
#Label(ioframe, text=" output file:").pack(side="left")
#soutfile = StringVar()
#soutfile.set("out.dat")
#Entry(ioframe, width=10, textvariable=soutfile).pack(side="left")
#Label(ioframe, text=" ").pack(side="left")
#quitbtn = Button(ioframe, text="quit")
#quitbtn.bind('<Button-1>','exit')
#quitbtn.pack(side="left")
ioframe.pack()

root.after(100,idle,root,canvas)
root.mainloop()