Siemens MC55 AT manual At&W

-It is not recommended to switch to autobauding from a bit rate that cannot be detected by the autobaud mechanism (e.g. 300 bps). Responses to AT+IPR=0 and any commands on the same line might be cor- rupted.

•Autobauding and bit rate after restart

The most recently detected bit rate is stored when the ME is powered down (with AT^SMSO). Therefore, each time the module is restarted the correct bit rate must be found as described above. Unless the bit rate is deter- mined, the following constraints apply:

-An incoming CSD call or a network initiated GPRS request cannot be accepted. This must be taken into account when autobauding and autoanswer mode (ATS0 ≠ 0) are enabled at the same time, escpecially if SIM PIN 1 authentication is done automatically and the setting ATS0 ≠ 0 is stored to the user profile with

AT&W.

-Until the bit rate is found, URCs generated after restart will be output at 57600 bps. This applies only to user defined URCs, such as "+CREG", "CCWA", "^SCKS" etc. The URCs "^SYSSTART", "^SYSSTART CHARGE-ONLY MODE" and "^SYSSTART ALARM MODE" will not be indicated when autobauding is enabled.

Note: To avoid any problems caused by undetermined bit rates in the direction from TA to TE we strongly recommend to configure a fixed bit rate rather than autobauding.

•Autobauding and multiplex mode

If autobauding is active you cannot switch to multiplex mode (see AT+CMUX).

MC55_ATC_V04.00	Page 94 of 475	3/17/06
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