User manual

GSM modem protocol for pCO
2
Carel code +030220330 Rel. 2.0 del 30/10/02
18
2. PROTOCOL USE REQUIREMENTS
To connect the pCO
2
to a GSM modem, both of them must meet the following requirements respectively.
2.1 pCO
2
requirements
1. The application program must be suited to manage a GSM modem.
2. The firmware (BIOS) must be version
2.29
or higher for the compatible modems listed in the table below, except for the
SIEMENS TC35 modem. For the latter modem the BIOS must be version 3.08 or higher. The last version is available in
the area Carel Top User, included in the EasyTools package.
3. It must feature the RS232 expansion card, Carel code PCO200MDM0 (see
Connections
).
2.2 GSM modem requirements
Not all GSM modems are compatible with the
. A study of various brands of modem has led to
the following results:
MODEM
TYPES MANUFACTURER COMPATIBILITY
GSM360 TELITAL NO
POCKET GSM DIGICOM YES
GSM 2702-D MICROTEL YES
WMOD2B* WAVECOM YES TESTED
FALCOM A2D* FALCOM YES TESTED
FALCOM A3D
3
FALCOM YES
M20 SIEMENS YES
TC35* SIEMENS YES TESTED
The wording TESTED means that the modem has been tested on the pCO²
.
Recommended GSM modems: those marked “TESTED” in the compatibility column in the above table.
In reference tot the above table, the non-tested modems are theoretically compatible, in the sense that the Hayes command set
implemented includes all the commands that the pCO
uses to manage the modem.
In general, the modem being used must comply with the following requirements described in detail in the subsequent
paragraphs:
1. the PIN code of the modem SIM card must be disabled;
2. the number of the Service Centre has to be already entered in the SIM card;
3. furthermore, the space dedicated to the storage of SMS messages on the SIM card should be free.
2.2.1 Disabling the modem flow control
Since the protocol ensures that the data are transmitted in binary and not ASCII format, they can take any value between 0
and 255. In order not to mistake the data with the XON and XOFF software flow control codes, software control flow on the
modem must be disabled.
WARNINGS:
• In the GSM modems indicated in the table as being compatible, except for the SIEMENS TC35 (Wavecom WMOD2B,
Falcom A2, Siemens M20T) flow control is automatically disabled by the pCO
2
during the modem initialization phase when
the AT+IFC=2,2 extended Hayes command is sent.
3
GSM-GPS MODEM