MC55 AT Command Set
4.8 AT+CMUX s
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MC55_ATC_V01.05 Page 99 of 469 2/10/04
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4.8 AT+CMUX Enter multiplex mode
Syntax
Command Description
All information provided in this chapter applies to the ASC0 in terface only. The second interface ASC1 has no
support of Multiplex mode.
Multiplex mode according to the ETSI TS 101 669 and GSM 07.10 enables one physical serial asynchr onous
interface to be partitioned into three virtual channels. This allows you to take advantage of up to 3 simultaneous
sessions running on the serial interface. For example, you can send or re ceive data or make a call on the first
channel, while the other two channels are free to control the module with AT commands.
The MC55 module incorporates an internal multiplexer and thus integrat es all the functions needed to implement
full-featured multiplex solutions. For the application on top, custome rs have the flexibility to create their own mul-
tiplex programs conforming to the multiplexer protocol. To help system integrators save the time a nd expense of
designing multiplexer applications, SIEMENS AG offers WinMUX2k, a rea dy-to-use multiplex driver for Windows
2000 and Windows XP. Another approach is to develop customized solution s based on the sources of the
WinMux2k driver.
Test Command
AT+CMUX=?
Response(s)
+CMUX: (list of supported<mode>s)
OK
Read Command
AT+CMUX?
Response(s)
+CMUX: <mode>
OK
ERROR
+CME ERROR: <err>
Write Command
AT+CMUX=<mode>
Response(s)
OK
ERROR
+CME ERROR: <err>
PIN ASC0 ASC1 MUX1 MUX2 MUX3
! % % ! ! !
Reference(s)
GSM 07.07, GSM 07.10