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To transmit data via GPRS the application software uses a PPP stack. Windows uses it as a
part of a standard modem driver. In Windows these drivers are part of the Dial-up network.
However, application software which does not use the Dial-up network, can establish a PDP
context by executing a series of AT commands. Of course, you may also manually type
these commands using any terminal program. Afterwards the PPP stack is activated.
Discrete PDP context activation
Entering the PIN (AT+CPIN)
Refer to page 17.
Example:
AT+CPIN=1234 <RETURN>
OK
Defining a PDP context (AT+CGDCONT)
Refer to page 18.
Example:
AT+CGDCONT=1,ip,internet.t-d1.de <RETURN>
Defining a QoS profile (AT+CGQREQ, AT+CGQMIN)
Refer to page 18.
Example:
AT+CGQREQ=1,3,4,3,0,0 <RETURN>
AT+CGQMIN=1,3,3,3,0,0 <RETURN>
where the numbers correspond to <PDP context identifier>, <Service precedence>, <de-
lay class>, <reliability class>, <peak throughput rate>, <mean throughput rate >.
GPRS attach (AT+CGATT)
In order to use the GPRS service the GSM/GPRS modem must be GPRS attached. From
that moment on the PLMN knows that the GSM/GPRS modem is GPRS capable. This
means the GSM/GPRS modem can initiate a GPRS data call and Mobility Management
routines apply.
Example:
AT+CGATT=1
OK
GPRS AT commands
NOTE
The GPRS attach may already be done before the PDP context and the QoS profile
definition.
Appendix
