I have an iMac with Mojave (10.14.4).
The last system upgrade occurred about 4 weeks ago.]
I am using Arduino IDE 1.8.9.
I have previously programmed Uno, Mega2560R3 and Feather MO with this setup.
Until about a hour ago, there have been no issues with this setup.
Up until about an hour ago.
Starting with a new instance of the IDE, I plug in a MEGA2560R3. I select the correct board type. The port then tells me that I am connected to "/dev/cu.usbmodem14151201". I then upload a sketch and it executes. Board connecttion is USB type B
I then unplug the MEGA2560R3, plug in a Feather MO and select the correct board type. The port tells me its connected to "/dev/cu.usbmodem14151201" ( I THINK there were the same numbers but can not be 100% certain. Board connection is Micro USB type B
About one hour ago.
Starting with a new instance of the IDE, I plug in the MEGA2560R3 and select the correct board type. The port comes up with, as above, "/dev/cu.usbmodem14151201". Upload, execute, etc.
Now, I MAY have not disconnected (I can't be sure) the MEGA before switching over to the Feather MO. I plug in the Feather MO, select the correct board type and the ONLY selection for the port is "/dev/cu.Bluetooth-Incoming-Port". The previous port of "/dev/cu.usbmodem14151201" is not displayed.
Cables that are in use when the problem occurred are the same cables that have been used for the last several month. I've done the computer reboot a couple times. I've restarted the IDE several time, always with the same result - the MEGA shows up with a usb port available but the Feather MO does not.
Any ideas on what is happening would be greatly appreciated.