Restrictions On Multiplex Mode; Table 4.1: Availability Of At Commands On Virtual Channels - Siemens MC55 Command Set

MC55 AT Command Set
4.8 AT+CMUX
Refer to [5] which provides a detailed description of the multiplex architecture and step-by-step instructions of
how to install and configure the multiplex mode. The WinMUX2k driver and its source files can be supplied on
request. Please contact your local distributor to obtain the latest installation software and user's guide.
Parameter Description
(num)
<mode>
Multiplexer transparency mechanism
0
(num)
<subset>
Subparameters defined in GSM07.07 are adjusted for control and logical channels as follows
0
Notes
• The write command is used to enter the multiplex mode. The setup of the logical channels is initiated by the
TE, i.e. the TE acts as initiator. This means that the TE shall ensure that logical channels are established
before any further actions on the channels can be started.
• There is a timeout of five seconds, if the multiplexer protocol is enabled and no multiplexer control channel is
established. The GSM engine returns to AT command mode.
• The parameter maximum frame size (N1) of
All other parameters are not available.
4.8.1

Restrictions on Multiplex mode

When the serial interface ASC0 is in multiplex mode, data and fax calls can only be set up on logical channel 1.
Due to this restriction, AT commands have a different behavior on channels 2+3 compared to channel 1. Several
commands are not available, others return different responses. This chapter summarizes the concerned com-
mands. For general rules and restrictions to be considered in Multiplex mode please refer to [5].
Table 4.1: Availability of AT Commands on Virtual Channels
Command
+++
AT+CBST
AT+CRLP
AT+CG... (GPRS commands)
AT+F... (Fax commands)
AT&S
ATA
ATD
ATDI
ATL
ATM
MC55_ATC_V01.05
Confidential / Released
Basic option
UIH frames used only (control channel)
AT+CMUX
Behavior on channel 1
not usable, but see note
as described
as described
as described
as described
as described
as described
as described
as described
as described
as described
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in GSM07.10 is fixed to 97 and cannot be changed.
Behavior on channel 2+3
2)
not usable, but see note
not usable
not usable
see note
not usable
not usable
no Data Calls
no Data Calls
not usable
not usable
not usable
s
m
obile
2)
3)
2/10/04