ZyXEL Communications 2864 - Manual (Page 194)

16–18
• AT+VSM=< cml >
This command causes the DCE to select a compression method as follows:
The DCE returns the OK result code if the DCE accepts this command, or it re-
turns the ERROR result code if the value is out of range.
• AT+VSM?
This command causes the DCE to report the current compression setting in the
following form:
;;
OK
where
is the compression method label.
is the silence compression sensitivity.
is the voice sampling rate.
• AT+VSM=?
This command causes the DCE to report the compression methods supported. The
response is as follows:
2;ADPCM;2;0;(9600)
3;ADPCM;3;0;(9600)
30;ADPCM;3;0;(9600)
4;ADPCM;4;0;(9600)
OK
The first item in each line is the compression method label, the second item is the
compression scheme, the third item is the number of bits per sample, the fourth
item is the silence detection threshold level, and the fifth item is the sampling rate.
• AT+VTD=< dur >,
This command causes the DCE to set the default DTMF tone generation duration
<
dur > and comma pause intercal < int > used in conjunction with AT+VTS com-
mand.
The range of and is from 0 to 255. The units are 10 msec. The default
value for is 50 (500 ms) and for is 7 (70 ms).
The DCE returns the OK result code if the DCE accepts this command, or it re-
turns the ERROR result code if any of the < dur > or < int > values is out of range.
Compression Method Description
2 ZyXEL 2-bit ADPCM (default)
3 ZyXEL 3-bit ADPCM
30 ZyXEL new 3-bit ADPCM
4 ZyXEL 4-bit ADPCM