Using with Campbell Scientific Dataloggers
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9. Using Loggernet for GSM dial-up
These instructions apply to Loggernet. They also apply to software products
based on Loggernet, that support telephone modem or TAPI connections,
e.g. PC400.
9.1 Configuring a desk-top modem as a base station
You can use most desktop landline and even cell phone modems to connect
to a remote COM111 modem. The modem should be setup as if calling a
remote landline modem. The baud rate for connection should be set to 9600
minimum.
The modem can be configured to connect either via the TAPI or Phone
modem settings (TAPI being the preferred option if you have installed the
modem into your Windows environment.)
While Campbell Scientific Ltd may be able to give some
advice as to the best settings to use for common modems, the
connection of the landline modem to a cellular network is
specific to the cellular network being used. Problems
establishing the connections are often not related to the fact
that a COM111 modem or data logger are connected at the
remote end of the connection, but are caused by compatibility
issues of the PC modem with the network. Please also contact
your cellular network support team for advice on any problems
that you might encounter.
9.2 Configuring the COM111 modem as a base station using
Loggernet
Neither Campbell Scientific nor the manufacturer provide specific drivers
for the COM111 modem. Instead they recommend that you follow the
normal Windows procedure for installing a TAPI modem and select the
modem type “Standard 9600 bps” or “Standard 19200 bps”. Check that
Windows finds the modem and attaches it to the correct COM port. For this
to work you must make sure the baud rate of the modem has been setup
previously to match the modem type selected. Thereafter you can use the
modem to call-out using the TAPI interface.
You can also use the Phone modem option in Loggernet, using the default
modem type, with the baud rate set to 9600 baud. This option is preferred if
additional modem settings are required (see below) or if the COM111
modem is often unplugged from the PC, as the TAPI interface expects to
find the modem connected at all times.
Before use it is also necessary to reconfigure the modem back
to its factory default settings using a terminal emulator and
issuing the AT&F, AT+IFC=2,2, then the AT&W commands.
9.2.1 Extending the default time-outs
When using either a landline base modem or a COM111 modem as the base,
it is sometimes necessary to increase the time both the PC and the base
modem will wait before timing out an attempted connection to a remote
NOTE
NOTE
