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Siemens Brodersen MC55 AT User Manual

Page 94

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MC55_ATC_V04.00

Page 94 of 475

3/17/06

Confidential / Released

- 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

).