Yealink SIP-T54S Administrator's Manual page 413

Phone User Interface
Details of Configuration Parameters:
Parameters
account.X.auto_answer
Description:
Enables or disables auto answer feature for account X.
0-Disabled
1-Enabled
If it is set to 1 (Enabled), the IP phone can automatically answer an incoming call.
X ranges from 1 to 16 (for SIP-T54S/T48G/T48S/T46G/T46S/T29G)
X ranges from 1 to 12 (for SIP-T52S/T42G/T42S)
X ranges from 1 to 6 (for SIP-T41P/T41S/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)
X is equal to 1 (for SIP-T19(P) E2/CP860/CP920)
Note: The IP phone cannot automatically answer the incoming call during a call or while
dialing even if auto answer is enabled.
Web User Interface:
Account->Basic->Auto Answer
Phone User Interface:
Menu->Features->Auto Answer->Line X->Auto Answer
features.auto_answer.first_call_only
Description:
Enables or disables the IP phone to handle the incoming call arriving when the phone is in
another call or is dialing like a normal call.
0-Disabled
1-Enabled
If it is set to 0 (Disabled), the incoming call will be automatically answered if you end the
current call or cancel the dialing.
If it is set to 1 (Enabled), the phone rings if you end the current call or cancel the dialing.
You have to manually pick up the incoming call.
Configuring Basic Features
http://<phoneIPAddress>servlet?p=features
-general&q=load
Configure auto answer and auto answer
mute.
Permitted Values
0 or 1
0 or 1
Default
0
1
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