Yealink SIP-T54S Administrator's Manual page 710

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
For SIP-T29G/T27P/T27G:
X ranges from 1 to 6, Y ranges from 1 to 20, 22 to 40 (Ext key 21 cannot be configured).
Web User Interface:
Dsskey->Line Key/Programable Key->Label
Phone User Interface:
Menu->Features->DSS Keys->Line Key X->Label
linekey.X.shortlabel
(X ranges from 1 to 21)
Description:
(Optional.) Configures the short label displayed on the LCD screen for line key.
Note: It is only applicable to SIP-T52S IP phones.
Web User Interface:
Dsskey->Line Key->Short
Phone User Interface:
Menu->Features->DSS Keys->Line Key X->Short Label
linekey.X.extension/
programablekey.X.extension/
expansion_module.X.key.Y.extension
Description:
Configures the channel of multicast paging group.
For line keys:
X ranges from 1 to 29 (for SIP-T48G/S)
X ranges from 1 to 27 (for SIP-T54S/T46G/T46S/T29G)
X ranges from 1 to 15 (for SIP-T42G/T42S/T41P/T41S)
X ranges from 1 to 21 (for SIP-T52S/T27G)
X ranges from 1 to 3 (for SIP-T40P/T40G/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
For programable keys:
X=1-10, 12-14 (for SIP-T54S/T48G/T48S/T46G/T46S)
X=1-10, 13 (for SIP-T52S/T42G/T42S/T41P/T41S/T40P/T40G)
X=1-14 (for SIP-T29G/T27P/T27G)
X=1-10, 14 (for SIP-T23P/T23G/T21(P) E2)
X=1-9, 13, 14 (for SIP-T19(P) E2)
X=1-6, 9, 13 (for CP860/CP920)
684
Parameters Permitted Values
String within 99
characters
String within 256
characters
Default
Blank
Blank