When single mode is selected the call originating and hang-up procedures are similar to procedures specified in ITU-T Recommendations V.25ter, T.31 and T.32. In GSM there can be voice followed by data (refer to GSM 02.02), alternating voice/data (refer to GSM 02.02) and alternating voice/fax calls (refer to GSM 02.03).

Test command returns values supported by the TA as a compound value.

NOTE! - +CMOD is set to zero after a successfully completed alternating mode call. It is set to zero also after a failed answering. The power-up, factory (&F) and user resets (Z), also set the value to zero. This reduces the possibility that alternating mode calls are originated or answered accidentally.

<mode> Description

0Single mode. Default value.

In order to avoid accidental originating or answering of alternating calls is <mode> set to single mode in following cases:

-after a successfully completed alternating mode call;

-after a unsuccessful answering;

-after successfully execution of the commands &F and Z

Note!_

2.11AT+CVHU Voice Hang-Up

Description

Command

Possible Responses

Set Command

+CVHU=[<mode>]

Read command

+CVHU?

Test if the command is +CVHU=? supported

•_ +CME ERROR: <err>

•_ OK

•_ +CVHU: <mode>

•_ +CME ERROR: <err>

+CVHU: (list of supported <mode>s)

Selects whether ATH or “drop DTR” causes a voice connection to be disconnected or not. Voice connection also includes alternating mode calls that are currently in voice mode.

NOTE! - When <mode>=2, this command must be viewed in conjunction with the V.25ter command &D, or &D will be ignored.

Owner’s Manual

Rev 1.0

Page 69 of 69