Specifications

SIM900 AT Command Manual
SIM900_AT Command Manual_V1.03 228 12/24/2010
attachment is automatically done by the
AT+CGACT Command.
Use the defined and activated CID
to get online. The mobile can be
connected using the parameters of
appointed CID or using default
parameter
AT+CGDATA="PPP",
1
CONNECT
The mobile supports Layer 2 Protocol (L2P) PPP only.
Note: If the mobile is NOT attached by AT+CGATT=1 and the CID is NOT activated before
connecting, attaching and activating is automatically done by the AT+CGDATA Command.
Some providers require using an APN to establish a GPRS connection. So if user uses the
Microsoft Windows Dial-Up Network and ATD*9… to connect to GPRS, user must provide the
context definition as part of the modem definition (Modem
properties/Connection/Advanced…/Extra settings.) As an alternative, user can define and activate
the context in a terminal program (e.g. Microsoft HyperTerminal) and then use the Dial-Up
Network to send only the ATD Command.