ZyXEL Communications Comet 3356, Руководство пользователя

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64 Voice Operation
volume by a value of 5 units. The <DLE>d code can be used to adjust the volume within
the range of 128-228. (See <DLE><u> and <DLE><d> in Section 9.3.2.)
<DLE><CAN>
Cancel. Sent during Voice Transmit Mode to indicate that the DTE has finished
transmitting a voice message and wants the modem to discard any remaining data in the
voice transmit buffer. The modem immediately purges its buffer, and then responds with
the VCON message entering Online Voice Command Mode. (This command is ignored
by the modem when not in Voice Transmit Mode.)
<DLE><EOT>
Voice Bytes Buffered Query. Sent during the transmission or reception of voice/audio
data, by embedding the command in the voice data stream, to learn the number of
corresponding bytes buffered by the DCE at the moment the <DLE><EOT> command is
received by the DCE. <DLE>XZBBC=n<DLE> is returned by the DCE, in which "n"
represents the number of bytes buffered as a two byte hexadecimal value.
<DLE><ETX>
Terminate. Sent during Voice Transmit Mode to indicate that the DTE has finished
transmitting a voice message. The modem completes transmission of any remaining data
in the voice transmit buffer before responding with the VCON message and entering
Online Voice Command Mode. (This command is ignored by the modem when not in
Voice Transmit Mode.)
9.2.6 Voice Record
To effect recording of a message received via a handset or microphone, the DTE must
configure the modem for Voice Mode (#CLS=8), and select the proper relay setup
(#VLS) to instruct the modem whether to use the auxiliary device. The modem responds
to the #VLS command by issuing a relay activate command to select the input device.
When a device other than the telephone line is selected, the modem immediately enters
Online Voice Command Mode (indicated by VCON). DTMF detection is therefore
enabled as soon as the DTE selects the device, such as a handset, although the user still
needs to physically pick up the telephone and press buttons. Even if the DTE has not
entered Voice Receive or Transmit Modes (#VTX or #VRX), these DTMF tones are
delivered via shielded codes identically to when a physical telephone connection exists
but the DTE has not yet commanded receive or transmit. When the DTE decides to
record the message, it issues the #VRX command and upon command receipt, the
modem immediately switches to Voice Receive Mode. Since the microphone or handset
is switched in, the modem immediately issues the CONNECT message indicating that
the modem has switched to Voice Receive Mode and is beginning the transfer of
ADPCM voice or PCM audio data as well as shielded DTMF tones, and other tones
and statuses.
In this recording state, the modem (if so configured) monitors for line silence. If the
#VSP period expires, the modem sends the <DLE>q or <DLE>s code to the DTE.