Multi-Tech Systems MMCModem GPRS (MTMMC-G) - Manual (Page 90)

Chapter 10 – Supplementary Services Commands
Multi-Tech Systems, Inc. Wireless GSM/GPRS AT Commands (Document Number S000293I) 90
Unstructured Supplementary Service Data +CUSD
Description: The USSD supplementary service is described in GSM 02.90. It is based on sequences of digits which
may be entered by a mobile user with a handset. A sequence entered is sent to the network which
replies with an alphanumerical string, for display only, or for display plus request for the next sequence.
This command is used to:
• Enable or disable the CUSD indication sent to the application by the product when an incoming
USSD is received
• Send and receive USSD strings
Values:
0 Disable the result code presentation
1 Enable the result code presentation
2 Cancel session (not applicable to read command response)
0 no further user action required (network initiated USSD-Notify, or no further information needed
after mobile initiated operation)
1 further user action required (network initiated USSD-Request, or further information needed after
mobile initiated operation)
2 USSD terminated by network
4 Operation not supported
is network string, converted in the selected character set
is the data coding scheme received (GSM TS 03.38).
Syntax: Command syntax: AT+CUSD = [ , [ ] ]
Note: In case of enabled presentation, a +CUSD (as direct answer to a send
USSD) is then indicated with:
+CUSD: [,, ]
Command Syntax To Send and Receive USSD: AT+CUSD= [, [,]]
Note: Please be aware that the send USSD command needs the user to re-enter
the parameter!
Values for Send and Receive USSD
The USSD string to be sent.
The default alphabet and the UCS2 alphabet are supported.
When the product sends a USSD, an OK response is first returned, the
intermediate +CUSD indication comes subsequently. In case of error, a +CUSD:
4 indication is returned.