Campbell Scientific COM200 Telephone Modem - Manual (Page 12)

COM200 Telephone Modem
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4. Troubleshooting
When the Campbell Scientific software cannot establish a link to the remote
datalogger that is connected to the COM200, check the following:
1) Verify the modem initialization settings have been changed for the
specific calling modem on the computer. See software manual and/or
help screens for more information.
2) Verify nothing else is using the same COM port on the computer. Even if
a program is minimized in windows, it may have a lock on the COM port.
Some notebook computers do not automatically activate the COM ports.
Verify the COM port you are using is activated.
3) The Campbell Scientific software will display an activity of
communication as the link is being established. Assuming the above
items are O.K., the software should display in the activity window/screen
something such as “ ATDT#######” . Where the #### is the telephone
number listed in the dialing path of the software for the datalogger you
are trying to call.
The local modem attached to the computer will respond back to the
computer with result codes depending on how the call is progressing.
These result codes can be either numeric (0, 1, 2, etc.) or “ verbose”
(“ OK” , “ CONNECT” , “ RING” , etc.). Our software expects numeric
result codes. The result codes may appear on a new line, be appended to
the last line, or may even replace the first letter(s) of the last line. If these
characters are verbose, the initialization string for the modem will need to
be changed. Appendix A has a list of possible result codes. The result
code returned may indicate why the call is unsuccessful.
4) Can you attach a normal analog telephone to the line and make a call out?
If not, contact your local telephone company. If you can make a call out
but the connection is poor or faint, contact your local telephone company.
5) Verify the COM200 is receiving 12 VDC. If the COM200 is receiving 12
VDC from a separate power supply instead of the datalogger, is the
ground of the separate power supply connected to the datalogger’s
ground?
6) Verify the COM200 is the only Modem Enable device connected to the
datalogger. Other common Campbell Scientific modem enable devices
are the SC32A, some RF modems, and the MD9.
7) Verify the datalogger is turned on.