Mac IDE 1.8.12 w/Connection Issues.

Forgive the novice post --

For the Leonardo -- I'm completely confused as to the board and processor selection.

From: https://store.arduino.cc/usa/leonardo
Select "Arduino Leonardo from the Tools > Board menu (according to the microcontroller on your board).
In the UI, there is no such entry in the available options.

The Leonardo shows a ATmega32U4 processor -- and the Boards Manager lists the Leonardo under the AVR boards selection ( 1.8.2 ) -- but this only provides me with 3 options (Uno, Mega and Nano) and none of these options show the 32u4 processor option (2560 and 328p).

If anyone has some suggestions on how to correctly identify the board for the IDE so I can work with it, your input is greatly appreciated.

My other connection issue is with a mega2560 -- which can connect, when the wind is blowing south.

It will connect, and if you quickly disconnect and reconnect, the serial port will remain.
However, if you unplug it for a few minutes, it cannot reconnect the serial port.
But if you leave it for another x minutes, it can connect again.

From my reading, this may a known issue with the Macs.
Were I to hazard a guess, it may be a timeout issue on a socket or file descriptor - and when that timeout has elapsed, a new socket is generated. Or it could be a board issue with memory?

For what it's worth, it's the smraza board provided here:

Ty.

As a quick update - the Web editor has Leonardo in the selection list, and it immediately connects.
Why does the Mac IDE not have the same options?

redherring:
Select "Arduino Leonardo from the Tools > Board menu (according to the microcontroller on your board).

This must be a copy/paste error from one of the other product pages. It should say:
Select "Arduino Leonardo" from the Tools > Board menu.

redherring:
this only provides me with 3 options (Uno, Mega and Nano)

Have you installed any 3rd party software modifications to the Arduino IDE, maybe like something for a 3D printer?

My CR10 uses an Arduino board --

After your comment, I thought it may have cached something, so I uninstalled and Deleted the /Library/Arduino15 folder ... no dice.

As it turned out, it was still picking up something from my documents folder -- a Libraries directory.
And once I removed that -- everything was golden.

Ty.

That said, how do you deal with library conflicts for different distributions?

I'm glad to hear you found the solution!

redherring:
how do you deal with library conflicts for different distributions?

What do you mean by "distributions"?

It looks like the TH3D package contains some libraries that may cause conflicts.

https://www.th3dstudio.com/knowledgebase/arduino-ide-for-mac-os-x-setup-guide/

I'll see if I reinstall if the libraries remove the other board options again.

Thanks again for your help.

Ugh, yeah I downloaded and installed that thing a few weeks ago and it is a mess. I hope the company is better at designing 3D printers than they are at providing software support for them.

I don't fancy doing that unnecessarily huge download again, but I think you're on the right track.