Entry Widget issue

[deanhystad]

while 1:
    arduinoData = ser.readline().decode('ascii')
    print(arduinoData)

#### NO CODE BELOW THIS LINE EVER RUNS ####
e = Entry(root,width = 100, textvariable = arduinoData ,borderwidth = 5)
e.grid(row = 0, column = 0, columnspan = 3,padx = 10,pady = 10)
   
 
root.mainloop()

You cannot block reading a serial port and have a GUI application. The GUI must be allowed to run. Either you need to do no-blocking serial reads and pool for data, or you need to launch a separate process to read the serial port. Neither is easy. Both types of solutions should be well documented because this is a fairly common problem.