User guide

V.250 AT COMMANDS
45 AT Commands for EV-DO-EV3 Modems
Disconnect H
Execute command closes the current conversation (voice or data).
Syntax
Command Command type
ATH Execute
Notes
 This command can be issued only in command mode; when a data conversation is active the device is in on-
line mode (commands are not sensed and characters are sent to the other party), hence escape sequence is
required before issuing this command, otherwise if &D1 option is active, DTR pin has to be tied Low to
return in command mode.
 Reference: V.25ter.
Compression Control
Data Compression Reporting +DR
Set command enables or disables the data compression reporting upon connection.
Read command returns current value of <n>.
Test command returns all supported values of the parameter <n>.
Syntax
Command Command type
AT+DR=<n> Set
AT+DR? Read
AT+DR=? Test
Parameters and Values
<n>
0 Data compression reporting disabled.
1 Data compression reporting enabled upon connection.
If enabled, the following intermediate result code is transmitted before the final result
code: +DR: <compression> The only supported value for <compression> is “NONE”.
Notes
 Reference: V.25ter
S Parameters
Basic commands that begin with the letter “S” are known as “S-Parameters”. The number following the “S”
indicates the “parameter number” being referenced. If the number is not recognized as a valid parameter number,
an ERROR result code is issued.
If no value is given for the subparameter of an S-Parameter, an ERROR result code is issued and the stored value
left unchanged.