I am using the MAC version of the IDE, and today hooked up a Nano 33 for the first time. It came up, accepted downloaded code, and worked fine. At that point, it was being powered by the USB connection.
Then I powered it through the Vin pin, with 12 v., and the port connection went away. I could no longer communicate with the N33. I have never noticed a problem like that with any other Arduino board. Is there a reason, or a workaround, for that?
Thanks in advance for any suggestions.