Panasonic KX-TDE100 - Manual (Page 203)

4.2 Feature Number Table
Operating Manual 203
Feature (While busy, DND or call tone is heard) Default
Call Waiting (BSS [Busy Station Signaling]) 1
DND Override
1.3.3 Alternate Calling—Ring/Voice
1.3.4 Automatic Callback Busy (Camp-on) 6
1.3.7 Call Monitor 5
1.3.23 Executive Busy Override 3
1.3.42 Message Waiting 4
Feature (While dialing or talking)
Fixed
Number
Conference 3
1.3.20 Door Open
From any extension while talking to the doorphone 5