Campbell Scientific COM200 Telephone Modem - Manual (Page 15)

A-1
Appendix A. Modifying the Non-Volatile
Memory
To modify the COM200’s settings, one must communicate directly to the
COM200. This may be accomplished by using one of the two methods below.
Changing some of the modem's settings may result in
communication problems. After changing the settings, try
the modem locally before installing it at a remote location.
A.1 Hardware Connection to COM200
Connect the COM200 to a computer using an SC532 interface (Figure A-1).
COM200s prior to S/N 2334 require the 10704 adaptor as shown in Figure A-
2. The computer software (PC208W) used to communicate with the COM200
must set the RS232 RTS line low.
For example, to change the COM200 to answer on the 3 rd ring, the following
commands would be sent to the COM200 through the PC208W terminal
emulator (RTS not active on modem hardware configuration):
ATS0=3
AT&W0
A.2 Remote Communication to the COM200
To remotely communicate with the COM200, program the datalogger to
initiate a call to it using a program similar to the Example Program 1.* After
this program runs once, the modem is now programmed and the actual
program one wants to run may now be downloaded to the datalogger.
*Please note that this program requires that the option code for an RF modem
be used instead of the normal phone modem option.
CAUTION