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ICS Remote Tools User Guide
Appendix A
Connecting a modem
This appendix provides information required for a remote connection from Norstar ICS Remote
Tools (ICSRT) to the RAD at 9600 baud.
Note: This does not apply to the FastRAD.
Hardware required
The following is a list of the hardware required at the remote Norstar ICS end:
•RAD
• Hayes compatible external modem 9600 baud or higher
• standard RJ11 telephone cable
• null modem cable or adaptor
• 25 pin RS-232 female/male gender changer may be required
• direct telephone line
Modem specifications
The modem must be configured from a computer prior to connecting it to the RAD. Modem
manufacturers use different commands for implementing the features listed below. For more
information, refer to the manual that came with your modem.
1 The modem must be set to answer at a maximum of 19200 Baud.
Note: The RAD will not communicate at speed higher than 19200.
2 The modem must be set to Auto Answer (the standard ‘ATS0=1’ command will work on all
Hayes Compatible modems).
3 The modem must be commanded to control the Data Set Ready (DSR) as per CCITT standards
(ITU-T). By default most modems come configured to with DSR High as Always ON.
4 The modem must be set to ignore the Data Terminal Ready (DTR) signal. The modem needs
to assume that DTR is Always ON.
5 The modem must be configured to allow the DTE/DCE rate to follow the link rate. This means
that the modem to RAD baud rate will be set to the same rate as ICSRT connects with the
modem. Since ICSRT will be set to connect at 9600 baud with this modem, the modem will in
turn communicate with the RAD at 9600.
