10
Configuring the off-hook mode
The FXO interface supports two off-hook modes:
• Immediate mode—Upon receiving a call, the FXO interface goes off-hook and sends a dial tone to
the calling party. Then, the calling party dials the destination number.
• Delay mode—Upon receiving a call, the FXO interface places a call to the specified private line
number. When the called party picks up the phone, the FXO goes off-hook. This mode needs to
work with the private line auto ring-down (PLAR) function. For more information about PLAR, see
"Configuring dial programs."
To configure the off-hook mode:
Ste
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter FXO interface view.
subscriber-line line-number N/A
3. Configure the off-hook mode.
hookoff-mode { delay |
immediate }
By default, the immediate mode is
used.
Configuring ring detection parameters
PBXs from different vendors use different types of ring signals. By setting ring detection parameters, you
can enable the FXO interface to detect ring signals of different frequencies and waveforms.
To configure ring detection parameters:
Ste
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter FXO interface view.
subscriber-line line-number N/A
3. Set the debounce time for ring
detection on the FXO
interface.
ring-detect debounce value
The default is 10 milliseconds.
• Do not set the debounce time
during a conversation.
• Do not set too short a debounce
time, because false ring tone
recognition might occur under
power line interference.
• If you configure this command
on an FXO interface of a card,
the configuration takes effect on
all FXO subscriber lines of the
card.
4. Set the frequency value for
ring detection.
ring-detect frequency value The default is 40 Hz.
