Many people seem to think that you can no longer use CAT mode on the new 8300 however NEC have added a new way of getting into CAT mode. With the phone on hook (idle) dial 2286633# then press hold. If you spell out CATMODE on the dial pad you will see where this comes from. This has been made necessary due to the conf key no longer appearing on the phone as default. I have been told that you can put a conf key on one of the line keys and access CAT mode that way but I have never personally tried it!
Unfortunately there is also a difference in the way the keys are used depending on the system software R1 software sees the keys come up in the following order...
A B C D E F
BLANK BLANK ST EXE CE S
, - <- DE BLANK BLANK
BLANK BLANK BLANK BLANK BLANK BLANK
However R2 and above sees them come up in this order.....
A B C D E F
. BLANK BLANK BLANK BLANK BLANK
ST EXE CE S BLANK BLANK
, - <- DE . BLANK
Also in R2 or later software you regain the use of the other keys for programming as listed below
Recall = DE Answer = S Feature = - Mic = . Hold = <- Transfer = , Speaker = CE Menu = ST Circular key centre = EXE Circular key up = - Circular key left = <- Circular keydown = S Circular keyright = DE
Just one note though, CAT mode is not available when preset dialing on the terminal is restricted (set by CM15 Y=212: 0).