Specifications

Chapter 4 – Voice Commands
Multi-Tech Systems, Inc. SocketModem MT5600SMI/MT5656SMI Reference Guide (S000306B) 108
Command: +VSD Silence Detection (Quiet and Silence)
Description: This command causes the modem to set the silence detection sensitivity and
the required period of silence before the modem reports silence detected at
the end of a voice receive either with the “Presumed End of Message” (QUIT)
or “Presumed Hangup (SILENCE) event reports.
Syntax: +VSD=<sds>,<sdi>
Defined Values: <sds> Decimal number corresponding to the selected parameter.
0 Use +VSM silence compression setting and algorithm for long-term silence
detection (if +VSM is in use) or proprietary silence compression setting and
algorithm for long-term silence detection (if +VSM is not in use).
127 Sets less aggressive long-term silence detection independent of
presence or use of silence compression.
128 Sets nominal long-term silence detection independent of presence or use
of silence compression.
129 Sets more aggressive long-term silence detection independent of
presence or use of silence compression.
<sdi> Decimal number specifying the required period of silence, in units of 0.1
second, before the modem can report silence detected at the end of a voice
receive either with the “Presumed End of Message” (QUIT) or “Presumed
Hangup (SILENCE) event reports. A value of 0 disables the modem silence
detection. The range is 0.1 to 25.5 seconds for <sdi> = 1 to 255.
Reporting Current or Selected Values:
Command: +VSD?
Response: <sds>,<sdi>
Example: 0,50 For the default setting.
Reporting Supported Range of Parameter Values:
Command: +VSD=?
Response: (<sds> range),(<sdi> range)
Example: (0,127-129),(0-255)
Result Codes: OK <hook> = 0 or 1.
ERROR Otherwise, or if not in Voice Mode.