Datasheet

use 32u4 or Arduino Zero
If you have a ItsyBitsy M0 (look on the board to read what it is you have) Make sure you select ItsyBitsy M0 - do not
use 32u4 or Arduino Zero
I'm having problems with COM ports and my Itsy/Feather 32u4/M0
Theres two COM ports you can have with the 32u4/M0, one is the user port and one is the bootloader port. They
are not the same COM port number!
When you upload a new user program it will come up with a user com port, particularly if you use Serial in your user
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