Hi, sorry I haven't replied before. I don't check this forum very often).
You will need CAP (Computerized Attendant Position) to do this. This will run on a PC and have an RS232 link to a KB port on the Coral (for programming of names) and an RS232 link to an APA on a 280D (or DKT2321) phone, there will also be an RS232 connection from the PC to Fidelio system (are you using a Equinox box?). You will also need authorization in the Coral for hospitality.
There's a bit of programming needed in the Coral, and CAP takes a bit of setting up.
Micros Fidelio will need to create an interface on their system for connection to CAP. You will need to talk to them to co-ordinate the port settings, usually 9600 N 8 1.
What country are you in?