Sony Ericsson GM28, Integrator'S Manual

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2. GM28 MODEM
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LZT 123 7468 R1A
2.3 GM28 in a Communication System
Figure 2.1 illustrates the main blocks of a wireless communication
system using the GM28. It also shows the communication principles of
the system. The definitions in the figure, as used elsewhere in this
manual, are in accordance with the recommendations of GSM 07.07.
• The MS (mobile station) represents the GM28 modem plus SIM
card. The modem excluding SIM card, is known as the ME (mobile
equipment).
• The TE (terminal equipment) is a micro-controller (i.e., a computer)
and is a part of the application.
Figure 2.1 Main Blocks in a Wireless System
In accordance with the recommendations of ITU-T (International
Telecommunication Union - Telecommunications Standardisation
Sector) V.24, the TE communicates with the MS over a serial interface.
The functions of the GM28 follow the recommendations provided by
ETSI (European Telecommunications Standards Institute) and ITU-T.
ETSI specifies a set of AT commands for controlling the GSM element
of the modem; these commands are supplemented by Sony Ericsson
specific commands.
To find out how to work with AT commands, see “Part 3: Using AT
Commands”, page 53.
TE
(DTE)
AT commands to control MS
ME status, responses
MS
(GM28)
GSM Network
Application
Wireless Communication System