Why does Bittle show as Mega Not Uno.
Does this matter?
That's what I don't understand. Bittle has nothing to do with Mega in both hardware and software. When producing the boards, we also uploaded an Uno code to test its modules and all the boards have passed the test. Did you burn the bootloader as Arduino Mega by accident?
Do you mean here?
I just selected Uno from the list after Arduino software installation