[Tkinter] Anyone know what happened to my button?

[IgnacioMora23]

Because I don't have an xbee available to play with, can't run the code, so unable to diagnose.
I actually do have a bunch of older xbee's that are in a tote in my garage, but it would take a few months to find them.

I think that you should unconditionally close the device in your finally clause.
If for any reason it was not closed, the next time the codigoIniciar() function was called, you would be trying to open an already open device, I have no idea what (if any) problem that would cause.

Maybe, I think it is the general loop en the GUI. Because I only want to call one One time the codigoIniciar() .