Rockwell RCV144ACx, Справочник по командам

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AT Command Reference Manual
1048 3-49
3.9 AUDIOSPAN AND DSVD COMMANDS
AudioSpan and DSVD are two technologies that allow simultaneous voice and data operation using a Rockwell modem
connected to a telephone line. AudioSpan and DSVD implementations differ in the manner that voice and modem data are
combined. Voice and data channels are combined in the analog domain for AudioSpan and in the digital domain for DSVD.
Establishing a AudioSpan or DSVD connection is analogous to establishing a regular data modem connection. Initiate the
call using normal dialing (ATD) and answering (ATA) procedures. The modem can switch from a regular phone conversation
into AudioSpan or DSVD mode and back to phone conversation. A handset, headset, or microphone/speaker can be used
for voice communication during AudioSpan or DSVD mode.
AudioSpan operates in normal (non-error corrected) or error-corrected/compression mode (MNP 5 or V.42 bis depending on
the error correction settings of the modems). The DTE rate must be equal to or greater than the anticipated DCE connection
speed. In general, DTE speed of 38400 bps or higher should be used.
3.9.1 Commands Supported by Both AudioSpan and DSVD
-SMS= x, y, z, t - Select AudioSpan/DSVD Mode
The x parameter selects Data, AudioSpan, or DSVD mode, or enables automatic mode selection. The y, z, t parameters are
optional and are required only if the user wishes to control connection speeds. For example, AT-SMS=2 is sufficient to
enable SVD.
x: AudioSpan/DSVD/Data mode select and automatic mode select enable
0 = Data mode
1 = DSVD mode (A modem not supporting DSVD will respond with ERROR)
2 = AudioSpan mode (A modem not supporting AudioSpan will respond with ERROR)
3 = Automatic mode select (DSVD/AudioSpan/Data) (Default)
Note: AT-SMS=1 performs the same operation at AT-SSE=1.
y: Minimum data speed (bps) with audio for AudioSpan mode (see y value in following table)
z: Maximum data speed (bps) with audio for AudioSpan mode (see z value in following table)
Modulation Selected (See -SQS Command)
y or z Value V.61 ML144 ML288
4800 S ( y and z Default) S (y Default) S (y Default)
7200 — S S
9600 — S (z Default) S
12000 — — S
14400 — — S (z Default)
S = Supported.
— = Not supported.
t: Symbol rate (ML288 modulation only)
0 = Auto Selection (Default)
1 - 6 = Reserved
The symbol rate must be set to 0 for for normal operation (default). The other symbol rate selections are for test
purposes only.