Siemens MC55 - page 101

MC55 AT Command Set

4.8 AT+CMUX s

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MC55_ATC_V01.05 Page 101 of 469 2/10/04

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1) Siemens GSM engines support the registers S0 - S29. You can change S0,S3,S4,S5,S6,S7,S8,S10 and S18 using the

related ATSn commands (see starting from ATS0). The other registers are read-only and for internal use only!

2) The applicability of the +++ escape sequence depends on the customer's external application based on the Mulitplexer

Protocol. Recommendations for implementing an appropriate modem status command (MSC) are provided in [5], Chapter

"Escape Sequence".

3) PDP contexts can be defined on any channel, but are visible and usable only on the channel on which they are defined

(thus it is not possible to define a context on channel 2 and activate it on channel 3). GPRS connections can be estab-

lished on two channels at a time.

Table 4.2: Summary of AT commands with Different Behavior in Multiplex Mode

ATO as described not usable

ATS6 1) as described not usable

ATS7 1) as described not usable

ATS8 1) as described not usable

ATS10 1) as described not usable

ATS18 1) as described not usable

Command Description

AT\Q It is recommended to use hardware flow control (AT\Q3). XON/XOFF flow control

(AT\Q1) is not supported in Multiplex mode.

See note regarding AT\Qn settings stored with AT&W if Multiplex mode is active.

AT&V Different default configurations on channels 1, 2 and 3.

AT&W Different user profiles can be stored on each channel.

AT+IPR Before you start Multiplex mode, it is recommended to set the ME to 57600 b ps

(minimum should be 4800 bps). For GPRS we suggest to use 115200 bps or

230400 bps.

In Multiplex mode, the write command AT+IPR=<rate> will not change the bit rate

currently used, but the new bit rate will be stored and becomes active, when the

module is restarted.

AT+IPR=0 Multiplex mode cannot be activated while autobauding is enabled.

AT+CALA On each channel an individual <text> message can be stored. but only one time

setting applies to all channels. This means an alarm <time> set on one of the

channels overwrites the time setting on all remaining channels. Therefore, the tota l

number of alarm events returned by the read command AT+CALA? will always be

<n>=0, no matter whether individual text messages are stored.

When the alarm is timed out and executed the ME sends the URC only on the

channel where the most recent alarm setting was made. The alarm time will be

reset to "00/01/01,00:00:00" on all channels.

AT+CMEE Presentation mode can be separately configured for each channel.

AT+CNMA If Multiplex mode is activated the +CNMI parameter will be set to zero on all chan-

nels, if one channel fails to acknowledge an incoming message within th e required

time.

AT+CNMI Phase 2+ parameters can only be used on one channel. The parameter for <mt>

and <ds> on the other channels have to be set to zero. If either a SM or a Status

Report is not acknowledged, all +CNMI parameter will be set to zero on all chan-

nels.

Command Behavior on channel 1 Behavior on channel 2+3