Product data

USRobotics
Command Reference
Voice Commands - 132
0 Start receive voice without periodic tone production during a voice
receive operation.
1 Start receive voice with periodic tone production during a voice
receive operation.
Result Codes
OK <n> = 0 or 1.
ERROR Otherwise, or if not in Voice Mode.
+VTR - Start Voice Transmission and Reception (Voice Duplex)
This command causes the modem to start the voice transmission and reception
process (Voice Duplex) without either acoustic echo cancellation or line echo
cancellation. The modem begins the Voice Duplex State by returning the
CONNECT result code to the DTE. The modem then sends <DLE> shielded voice
data to the DTE, and the DTE can send <DLE> shielded voice data to the modem.
The modem will accept data from the DTE and send data to the DTE in the format
previously selected by the +VSM command, and use the flow control method
selected by the +IFC command.
The modem signals termination of the voice data stream by appending a
<DLE><ETX> command and padding out to an octet boundary if needed. The
modem will issue the <DLE><ETX> character pair (thereby ending the modem to
DTE voice data flow) followed by the OK result code, and return to the command
mode after the modem has completely transmitted the contents of its buffer.
There are two methods to leave the Voice Duplex State: the DTE sending a
<DLE><^> shielded code or the inactivity timer elapsing in the modem. The Voice
Command State is entered upon Voice Duplex State termination.
This command will function when the input and output are from/to the same I/O
device, such as local handset, line, or mic/speaker.
Syntax
+VTR
Result Codes
OK Upon command acceptance.
ERROR The modem is not connected to the line and a non-line device.
+VTS - Send Voice Tone(s)
This command causes the modem to send DTMF digit or hookflash tones with the
duration specified by +VTD, to send DTMF digit or hookflash tones with duration
specified by this command, or to send single or dual tone frequencies with
duration specified with this command.