Yealink SIP-T48G Administrator's Manual page 159

Parameter
hotline feature.
Example:
features.hotline_number = 1234
Web User Interface:
Features->General Information->Hotline Number
Phone User Interface:
Menu->Features->Hot Line->Hot Number
features.hotline_delay
Description:
Configures the waiting time (in seconds) for the IP phone to automatically dial out
the hotline number.
If it is set to 0 (0s), the IP phone will immediately dial out the preconfigured hotline
number when you lift the handset, press the speakerphone key or press the line key.
If it is set to a value greater than 0, the IP phone will wait the designated seconds
before dialing out the predefined hotline number when you lift the handset, press
the speakerphone key or press the line key.
Web User Interface:
Features->General Information->Hotline Delay (0~10s)
Phone User Interface:
Menu->Features->Hot Line->Hotline Delay
To configure hotline via web user interface:
1. Click on Features->General Information.
2. Enter the hotline number in the Hotline Number field.
Configuring Basic Features
Permitted Values
Integer from 0 to 10
Default
4
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