Campbell COM110A, Руководство пользователя

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CS-GSM/GPRS Digital Transceiver Kits (including the COM110A modem)
6
9. Turn on the power to the datalogger and COM110A modem. The status LED
on the end of the package, near the SIM socket should come on continuously
initially. After a period of about 15 seconds the LED will start to flash
briefly every 2-3 seconds. When the LED starts to flash it indicates that the
modem has signed onto the phone network successfully. Note the frequency
of flashing will vary with the depending on the power state of the modem and
whether data is being transferred.
Start-up your PC and run PC400, Loggernet or your chosen communications
program. Set up an IPPort connection to the datalogger, following the instructions
for your software package to do this. Enter the IP address assigned to your SIM
and the port number to match the one you entered in step 5 above. If the IP
address is a public address you should then be able to make a test connection to
the logger using the connect tool in the program being used. If the IP address is
fixed, but private, you may have to open a VPN connection to the private network,
following details from your SIM provider, before attempting to make the
connection to the datalogger.
If the connection does not work, please refer to the fault finding section in this
manual.
The COM110A includes features to prevent it locking up and
going offline. However, there are still some rare events, e.g.
voltage surges or network reconfiguration from which it may
not automatically recover. For the highest reliability it is
therefore advisable to include code within your datalogger
program to reset the modem at regular intervals. Please refer
to Section 10 of this manual for more details of how to do this.
It is advisable to make sure you are running the latest operating
system in the datalogger before deploying a GPRS system to ensure
you have all the latest IP related features in the datalogger and to
ensure best reliability.
4. Using GSM Networks for Dial-up Data Transfer
This section discusses the principles of using the COM110A for GSM dial-up data
transfer in more detail.
GSM networks are based on international standards and are widespread
throughout the world – see the web site www.gsm.org. Theoretically a GSM
phone can be used anywhere in the world if it is within range of a GSM network
of the same frequency. For voice communications this theory almost works in
practice, except that many airtime providers (the company you pay for use of the
phone) limit the geographical range of most phones, and some do not have
agreements with distant providers.
For data transmission, most networks support the SMS (Short Message System).
This is not very practical for collecting large volumes of data, but can be useful for
sending alarm messages – see Technical Note 33 for more details of using SMS
with older loggers. Contact Campbell Scientific for details of sending or receiving
text messages with CRBasic dataloggers. (Please note that the COM110A modem
defaults to Text format SMS messages and as the message centre is normally
CAUTION
NOTE