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Siemens Brodersen MC55 AT User Manual

Page 272

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MC55_ATC_V04.00

Page 272 of 475

3/17/06

Confidential / Released

• When the

AT+CGAUTO

=1 command is received, the MT will attempt to perform a GPRS attach if it is not yet

attached. Failure will result in ERROR or, if enabled +CME ERROR being returned to the TE. Subsequently,

the MT announces a network request for PDP context activation by issuing the URC RING to the TE, followed

by the intermediate result code CONNECT. The MT then enters V.250 online data state and follows the same

procedure as it would after having received a +CGANS=1 with no

or

values specified.

• If a GPRS attach will be initiated by this command and the MT is not able to attach for more than 385 seconds

(timer T3310 expired), command returns with "ERROR" or "+CME ERROR: unknown", but MT is still trying

to attach and the requested automatic mode

is in use.

• If a network request for PDP context activation is answered automatically and if another AT command is

issued at the same time on the same interface, then this AT command is not executed. Any response belongs

to the automatic context activation procedure. If the AT command which caused the collision was a circuit

switched data call, the CONNECT response does not belong to this data call but to the GPRS. This can be

detected if

ATX

is not set to 0. CS data call will issue CONNECT , GPRS will issue CONNECT only.