Yealink SIP-T54S Administrator's Manual page 627

Configuring Advanced Features
Details of Configuration Parameters:
Parameters Permitted Values Default
linekey.X.type/
Refer to the
programablekey.X.type/ 38
following content
expansion_module.X.key.Y.type
Description:
Configures a DSS key as an LDAP key on the IP phone.
The digit 38 stands for the key type LDAP.
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/T27P/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)
For ext keys:
For SIP-T54S/T52S:
X ranges from 1 to 3, Y ranges from 1 to 60.
For SIP-T48G/T48S/T46G/T46S:
X ranges from 1 to 6, Y ranges from 1 to 40.
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).
Example:
linekey.2.type = 38
Default:
For line keys:
For SIP-T48G/S IP phones:
The default value of the line key 1-16 is 15, and the default value of the line key 17-29 is 0.
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