User`s manual

AT Command Reference Manual
1048 7-21
#VSP - Silence Detection Period (Voice Receive) [ADPCM]
This command sets the Voice Receive Mode silence detection period (inactivity timer) value. The parameter, in units of 100
ms, can be used when receiving voice data. This is an amount of time, which if elapsed without receiving any ADPCM data,
causes the modem to send the <DLE>s or <DLE>q codes after insuring that the buffer is empty.
The modem determines what constitutes silence. This involves monitoring and debouncing the modem value for average
energy. If this debounced value is less than an arbitrary threshold constituting the modem's definition of silence for a period
greater than that defined by the #VSP setting, the modem sends the <DLE>q or <DLE>s shielded code to the DTE.
Parameters: n = 0 – 255 (0 – 25.5 seconds)
Default: 55
Result Code:
OK If n = 0 – 255.
ERROR Otherwise.
Command options:
#VSP? Returns the current setting of the #VSP command as an ASCII decimal value in result code
format.
#VSP=? Returns the message, “0-255”.
#VSP=0 Turns off the silence period detection timer.
#VSP=n Where n defines the period without received voice data in 100 ms units.
#VSR - Sampling Rate Selection
This parameter, along with the bits per sample (#VBS) command, determines the necessary DTE interface speed to transmit
and receive in Voice/Audio Mode.
Parameters: n=7200 (7200 Hz sampling rate for ADPCM or PCM), or
n=11025 (11.025 kHz sampling rate for PCM only)
Default: 7200
Result Codes:
OK If n=7200, or if n=11025 and #VBS=8
ERROR Otherwise
Command options:
#VSR? Returns the current setting of the #VSR command as an ASCII decimal value in result code
format.
#VSR=? Returns the message "7200, 11025"
#VSR=7200 Selects 7200 Hz sampling rate
#VSR=11025 Selects 11.025 kHz sampling rate