I don't understand why my output from serial Monitor has unknown letters, I am sure it is caused by xbee.send(Tx64), if I command out xbee.send(TX64) those unknown letters disappear. could someone explain why this is happening and how may I correct it?
On the receiver side (python version) I can only receive 'NPK::::' I am not sure if this is cased by my first question.
I have the output from the serial Monitor and the code attached.