Comtrol AT Commands - Manual (Page 193)

AT Commands for CX81801/CX06833/CX81300/CX06827 Modems Reference Manual
102184B Conexant 5-17
+VSD - Silence Detection (Quiet and Silence)
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.