Chapter 4. Status Menu4-4 TSU 120 User Manual 61202129L1-1Figure 4-3. Display of Alarm MessageView HistoryThis menu item both displays and clears the accumulated sta-tus changes of the unit.View History displays a history of the first 20 status changes inthe unit, including the date, time, and type of change. The unitalso records for viewing, the date and time an alarm becameactive and inactive, as well as the date and time of test activa-tion and deactivation.To clear the View History display, press Clear (Shift+9) with theView History menu active.Port StatusPort Status displays the signals monitored on the data ports.For example, the Nx/DBU interface monitors the RTS, CTS,and RD, along with other signal lines. When a port is selected,the LCD indicates if the signal is present.The base Nx interface offers the status screen listed in this sec-tion. When using other option cards, refer to the appropriateseparate manual for a definition of any status screens offered.The Port Status of Nx/DBU is examined as an example of howto use this item. The DBU feature is available only in theTSU 120e.Alarm SourceAlarm Message
