Campbell COM110A, User Manual

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Using with Campbell Scientific Dataloggers
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5.5 Calling the logger in GSM dial-up mode when it is set for GPRS comms
In some circumstances it may be advantageous to call out to the system in GSM
dialup mode by dialling and connecting with a phone modem. This may be
necessary in the event of failure of the GPRS network or network connections that
prevent dial-back to the Loggernet server. It is possible to call the logger in the
standard way (see above) providing you know the GSM data phone number and
also providing the logger has periods of operation when the PPP connection is not
enabled, i.e. PPPClose has been called.
It is not possible to establish a GSM data connection whilst a PPP
session is in progress. It is not possible to call a COM110A in GSM
mode when it is configured for GPRS use.
5.6 Sending configuration commands to the modem
It is often advisable to reset the modem at regular intervals or send other
configuration commands to the modem, for instance to enable very low power
states between calls. When using the loggers IP Stack, this can be done within the
datalogger program by opening the serial port to which the modem is connected
and sending out commands using the serialout command. To allow another PPP
connection the program must close the serial port using serialclose otherwise the
PPP connection will be permanently blocked.
When using the Modem IP stack configuration commands are not normally sent
from the datalogger.
6. Installation of the COM110A modem
6.1 Configuring and Fitting the SIM
Before the COM110A modem can be used or tested, it must be fitted with a ‘SIM’
card (Subscriber Identification Modem) that enables it for use on a specific
cellular telephone network in a particular frequency band..
If possible, ensure that the SIM is configured so that it does not require a Personal
Identification Number (PIN) security code to be entered after the modem is
powered up. The PIN can most easily be disabled by inserting it into a separate,
hand-held standard GSM phone and following the instructions contained in the
phone manual. If a separate phone is not available, please contact Campbell
Scientific for details of how to disable the PIN code for use with the COM110A. If
this is not possible, or if your airtime provider only allows operation with a PIN
enabled, please refer to Appendix A.
Some SIM suppliers send the SIM with the PIN enabled and set to a
default PIN number. Check the documentation that came with your
SIM.
The SIM card is installed in the COM110A modem in the slot at the aerial end of
the case. Before installing the SIM make sure power is disconnected from the
modem. The SIM is installed in a small tray that has to be ejected by pushing in
the small green button which is to the rights of the slot holding the tray. Use a pen
or similar to push the button inwards. Insert the SIM with card with the gold
contact side of the card facing upwards in the tray. Ensure the cut-out of one
corner of the card is orientated to match the recess in the tray so the SIM sits flat
in the tray. Push the tray back into the slot until fully in then, with the aerial
NOTE
NOTE