In theory there's a PDF presentation and a video in apple documentation: https://developer.apple.com/documentation/corebluetooth/using-core-bluetooth-classic. But even though I'm trying to follow it I haven't been able to make it work yet.

Hi Adam, did you solve this issue? I'm having the same problem, in my case I'm not specifying any CBUUID because I'm only interested in the connection/disconnection itself, services and characteristics are not really relevant. Thanks!