How to raise frame in setInterval

Question

from Tkinter import *
from threading import Thread
from time import sleep

def call_at_interval(period, callback, args):
    while True:
        sleep(period)
        try:
            callback(*args)
        except:
            exit(0)

def setInterval(period, callback, *args):
    Thread(target=call_at_interval, args=(period, callback, args)).start()
def go():
    print("count")
    setInterval(3,count,5)

def count(val):
    i[0] = i[0] + 1
    print(i)
    if(i[0]%val == val-1):
        f2.tkraise()
    elif(i[0]%val==0):
        f1.tkraise()



i = []
i.append(1)
root = Tk()
f1 = Frame(root)
f2 = Frame(root)

for frame in (f1,f2):
    frame.grid(row=0, column=0, sticky='news')

f1.tkraise()
b = Button(f1,text="changeframe",command=go)
b.pack()
root.mainloop()

The all i want is to raise a frame from a function which is running on a certain interval of time during specific condition.An example is above.There is a problem in above example that when value of i[0] reach the val-1 it the setInterval stops and the application gives "not respondng error".Please any help me to short out this problem.