Board definitions for ATmega32u4 using internal 8MHz clock?

Other Hardware 3rd Party Boards
3

  1. Don't expect the USB interface to work if you are using the internal oscillator. The USB interface needs an accurate clock.

  2. The standard ATmega32u4 is shipped with the fuses set for the low power crystal oscillator (the ATmega32u4RC is the version set to use the internal oscillator initially). So you will need to supply either a crystal or an external clock initially, in order to change the fuses to use the internal oscillator.