Ring DetectionMost modems produce an interrupt request each time they detect a ring signal. Some modems generatean interrupt only on the first ring signal that they receive. AT&T DataPort 2001 is an example of such amodem.The service processor uses the ring interrupt request to count the number of rings when Ring IndicatePower-On (RIPO) is enabled. If your modem produces an interrupt on only the first ring, set Ring IndicatePower-On to start on the first ring. Otherwise, you can choose to start Ring Indicate Power-On on any ringcount.Terminal EmulatorsThe service processor is compatible with simple ASCII terminals, and therefore compatible with mostemulators. When a remote session is handed off from the service processor to the operating system,agreement between terminal emulators becomes important.The server’s operating system will have some built-in terminal emulators. You may also have acommercially available terminal emulation. It is important that the local and host computers select thesame or compatible terminal emulators so that the key assignments and responses match, ensuringsuccessful communications and control.For best formatting, choose line wrap in your terminal emulator setup.Recovery ProceduresSituations such as line noises and power surges can sometimes cause your modem to enter an undefinedstate. When it is being used for dial-in, dial-out or ring indicate power-on, your modem is initialized eachtime one of these actions is expected. If one of these environmental conditions occur after your modemhas been initialized, it might be necessary to recover your modem to a known state.If your modem communicates correctly with remote users, it is probably in control. It may be wise tooccasionally change some of the functional settings and then change them back, just for the sense ofsecurity that the modem is communicating, and to ensure it has been initialized recently.If your system is particularly difficult to access physically, another strategy is to protect it with anUninterruptible Power Source (UPS) and a phone-line surge protector.In case recovery becomes necessary, shut down your system using established procedures. Disconnectthe power cable and press the power button to drain capacitance while power is disconnected. Disconnectand reconnect modem power, and then reconnect system power to completely reinitialize your system.438 EserverpSeries 615 Service Guide
