Chapter 3: Printer Menus and the Control Panel 3–75DTR Function continued...Offline: When this option is active, the DTR Line is used to signal only that theprinter is Online or Offline. Unlike the Busy option, the Offline option will notinterfere with operation of the Xon/Xoff Communication Protocol.Power: When this option is active, the DTR Line is used to signal the host thatthe printer is powered up. This DTR Selection will not interfere with host recep-tion of the Xoff/Xon Serial Protocol, because unlike the Busy selection, the DTRSignal is not toggled at the same time as the Xoff Signal. When using this option,the DTR Polarity parameter must be set to Actv Hi.If your system is configured to use Xon/Xoff Protocol, using the Busy option above will cause interfer-ence with printer to host communication. You may however, use the DTR Line to signal the host thatthe printer is Offline or that the printer is powered up (Offline and Power options, respectively).DTR PolarityThis parameter is used to set the DTR Signal polarity. Active Low is the default.Busy PolarityThis parameter allows you to control the polarity of the Busy Signal. Active Lowis the default.RTS FunctionThe RTS line of the serial interface has been used to indicate Busy in addition tothe DTR line. This option allows the RTS line to either be continuously High orto function as Busy (default).Robust XonThis parameter behaves the same as a normal Xon/Xoff protocol, except thatwith this parameter enabled, the Xon code will be sent every 5 seconds when theprinter is ready to accept data. OFF is the default.Config Menu⇒ Serial I/O
