Chapter 17 – Extended AT Commands in IS707.3
Multi-Tech Systems, Inc. CDMA Wireless AT Commands - PN S000294C 141
Um Interface Data Compression +CDS Description: This command is an overloaded command that serves as an unsolicited SMS command and
also as a data compression command. The unsolicited SMS command is explained in
Chapter 3. The data compression command has an extended-format numeric parameter that
is used to control the V.42bis data compression function on the Um interface. The command
format is the same as for the TIA/EIS/IS-131 +DS command.
Syntax: Command syntax: AT+CDS=<Val>
Command Possible Responses
AT+CDS?
Note: Display the current setting.
+CDS: 0, 1, 2048, 6
OK
Note: Command is valid
AT+CDS=?
Note: Display the range of setting.
+CDS: (0-0),(1-1),(512-65535),(6-250)
OK
Note: Command is valid
Note: Currently, mobile only accept 0 as a valid setting.
Set Rm Interface Protocol +CRM Description: The numeric parameter is used for set the Rm interface protocol.
Values: <Val> 0: Asynchronous Data or Fax
1: Packet data service, Relay Layer Rm interface
2: Packet data service, Network Layer Rm interface, PPP
Note: The values 3 and 4 are currently not supported.
3: Packet data service, Network Layer Rm interface, SLIP
4: STU-III Service
Syntax: Command syntax: AT+CRM=<Val>
Command Possible Responses
AT+CRM?
Note: Display the current setting.
+CRM: 0
OK
Note: Command is valid
AT+CRM=?
Note: Display the range of setting.
+CRM: (0-2)
OK
Note: Command is valid
AT+CRM=1
Note: Set to 1.
OK
Note: Command is valid
Note: This default value for the +CRM parameter shall be 0 if this value is supported by the
DCE.