Appendix C: Modem Settings for RS-232 Dial-up PPP BackupC-2CyberSWITCH CSX400 and CSX400-DC Installation GuideThe caller side must be configured for the following:• DTR off to on transition causes modem to automatically dial previously stored phone number.• Data mode of operation set to call placed using the asynchronous call establishment commandset. Once the call connection is established switch to synchronous mode for transmission.• DSR follows/tracks CD.Using the Extended AT(tention) command set listed in the following table to configure the modem:(Note that each command is preceded by the AT keyword. For example, AT&C1.)To verify that the settings have been saved, power down the modem, then power it up again andenter the AT&$ command, and then the AT% command.Command Action&C1 Carrier on after link established (normally the default setting).&D2Enables automatic dialing. When:DTR on - go off hook (place call).DTR off - go on hook (hang-up).&M1 Selects asynchronous command mode/synchronous data mode.&R1 Selects Real synchronous mode, Real asynchronous mode, and AT commandmode (normally the default setting).&S2 Sets DSR to follow Carrier Detect (CD).%Z1 Enables automatic dialing when DTR off-to-on.&Z1=nnnStore the specified remote phone number, including any dial command modifiers.e.g., the area code in user configuration profile number 1. Up to nine digits can beentered, i.e., n= 0 to 9.&Y1 Selects user configuration profile #1 to load as the default profile at power-up.&W1 Save the above settings as user configuration profile number 1.&$ List the AT& command set settings to verify the configuration.%$ List the AT% command set settings to verify the configuration.
