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APPENDIX I
CSD connection:
CSD stands for Circuit Switched Data, it is a data transmission protocol over GSM
networks. To establish a CSD connection between two modem-equipped devices (like
WirelessCom/G10), one of the modems should initiate a call (dial-up). The procedure is the same as
making a voice call. Just dial the phone number of the modem with which you want to establish a
connection. (Connection is possible only if both the modems are GSM modems, a connection
between an analog modem and GSM modem may not be successful) and the other modem should
answer the call (it can be automatic or call will have to be answered manually). The steps for
establishing a CSD call with a WirelessCom/G10 is explained in the following section. Before
starting with the following steps make sure you have read the complete users manual.
1)
Enter into the configuration console of WirelessCom/G10 (as explained in the section 7.1-
7.3 of user manual).
2)
Configure the device for CSD connection, or you can use the default profiles csd_slave or
csd_master. Configure the authorized phone number (necessary if you are planning to make
a CSD connection in master mode) and CSD phone (necessary if you are planning to make a
CSD connection in slave mode).
3)
Once you have configured all the necessary parameters, test the device by entering the test
command. The testing command will help you to analyze the working of modem with your
configured parameters.
A)
Slave mode:
If you are testing the device in slave mode, it will perform various steps (after you have
entered the test command) and if everything is OK then it will wait for an incoming call. If
you want to make a data transfer then you should have another GSM modem and dial-up the
*phone number of WirelessCom/G10. (Remember to configure the phone number of dialing
modem in the authorized phone number of WirelessCom/G10). If you have configured the
settings properly then you would see RING on the terminal program screen and after end of
third ring WirelessCom/G10 will answer the call. Once the connection is established you
can make a data transfer.
B)
Master mode:
If you are testing the device in master mode, it will perform various steps (after you have
entered the test command) and if everything is OK it will make a CSD call to the *phone
number which is configured in csd_phone. If the receiver modem answers, the connection
