6-20 WAN Screens317517-A Rev 006.10 Advanced Modem Setup6.10.1 AT Command StringsFor regular telephone lines, the default “Dial” string tells the modem that the line uses tone dialing.“ATDT” is the command for a switch that requires tone dialing. If your switch requires pulsedialing, change the string to “ATDP”.For ISDN lines, there are many more protocols and operational modes. Please consult thedocumentation of your TA. You may need additional commands in both “Dial” and “Init” strings.6.10.2 DTR SignalThe majority of WAN devices default to hanging up the current call when the DTR (Data TerminalReady) signal is dropped by the DTE. When the “Drop DTR When Hang Up” check box isselected, the Contivity 221 uses this hardware signal to force the WAN device to hang up, inaddition to issuing the drop command “ATH”.6.10.3 Response StringsThe response strings tell the Contivity 221 the tags, or labels, immediately preceding the variouscall parameters sent from the WAN device. The response strings have not been standardized;please consult the documentation of your WAN device to find the correct tags.6.11 Configuring Advanced Modem SetupClick the Edit button in the Dial Backup screen to display the Advanced Setup screen shownnext.Consult the manual of your WAN device connected to your dial backup port forspecific AT commands.
