Configuration commands for voice mode operation – ZyXEL Communications 2864 User Manual

Page 190

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• AT+VTX

This command causes the DCE to start the voice transmission process. The DCE
begins the Voice Transmission Mode by returning the

CONNECT

result code to the

DTE. After this report, the DCE accepts shielded voice data from the
DTE. The DTE shall send the data in the format previously selected by the

+VSM

command and use the flow control method selected by the

+FLO

command.

There are two ways to leave the Voice Transmission State:

(1)

The DTE sends a shielded code.

(2)

A DTE/DCE Inactivity Timer time-out.

Item (1) is the DTE-initiated means of terminating the Voice Transmission State,
and item (2) is a DCE-initiated means of terminating the Voice Transmission State.
Upon termination of the Voice Transmission State, the DCE sends the

result

code and returns to the Voice Command State.

Configuration Commands for Voice Mode Operation

• AT+VGR=<

gain

This command causes the DCE to set the gain for the received voice samples. The
receival gain is an unsigned octet value. The normal value is 128. A value larger
than 128 indicates a larger gain than normal, and a value smaller than 128 indicates
a gain smaller than normal. A gain value of 56 corresponds to -18dB gain, 128 for
0dB, and 200 for 18dB, in 0.25dB steps. A value of zero invokes Automatic Gain
Control on the DCE. The gain range is 56 to 200 and the default value is 0.

The DCE returns the result code

if DCE accepts this command, or it returns

the result code

ERROR

if the <

gain

> parameter is out of range.

• AT+VGR?

The DCE will return the current receival gain, followed by the

result code.

• AT+VGR=?

The DCE will return all permitted values for the receival gain. The response is:

56-200
OK

• AT+VGT=<

level

This command causes the DCE to set the volume level, either by amplifying or at-
tenuating the signal, for the transmitted voice samples. The transmission gain (or
attenuation) is an unsigned octet value. The default value is 128. A value larger
than 128 indicates a larger gain than normal, and a value smaller than 128 indicates
a gain smaller than normal. The level range is 56 to 200. A gain value of 56 corre-
sponds to -18dB gain, 128 for 0dB, and 200 for 18dB, in 0.25dB steps.