C55/C55i AT COMMAND SET Description Preliminary - Falcom

C55/C55I AT COMMAND SET VERSION 1.00
- The serial interface shall be used with 8 data bits, no parity and 1
stop bit (factory setting), e.g. 2 stop bits are not supported for
autobaud mode.
- The command A/ cannot be used.
- Only the strings "AT" or "at" can be detected (neither "At" nor
"aT").
- URCs that may be issued before the ME detects a new bit rate
(by receiving the first AT character) will be sent at the
previously detected bit rate or, after ME restart, at 57600 bps.
- It is not recommended to switch to autobauding from a bit rate
that cannot be detected by the the autobaud mechanism (e.g. 300
bps). Responses to AT+IPR=0 and any commands on the same
line might be corrupted.
• 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 determined, 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 (ATSO≠0) are enabled at the
same time, especially 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" 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 DCE to DTE we strongly recommend to
configure a fixed bit rate rather than autobauding.
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