Most print devices now support bi-directional communications in a local area network (LAN) to provide feedback to print servers. This information is used in various dialog boxes (for example, for printer status and current job information). In Windows NT, bi-directional communication between a print device and a print server over the network can be accomplished if the following conditions are met:
- The print device can signal back to the print server (it is a PJL-compatible print device).
- You are using a communication channel or network protocol that can carry the signal.
- The print server is using the Windows NT Hewlett-Packard (HP) Network Print Monitor (HPMON) that expects the signal.
PJL-Compatible Print DeviceWhen communicating with HP's Printer Job Language (PJL) compatible print device (such as an HP LaserJet IIISi or HP4-series print device) the printer driver embeds a PJL command in the data stream that causes the print device to send a signal back to the print server. The signal notifies the server when the page has finished printing. If the print device understands PJL, bi-directional printing communication over the network is possible (HPMON must be used in Windows NT). If your print device does not recognize PJL, you must create a print monitor for Windows NT that can accept a signal sent from the print device.
Network ProtocolMost network protocols support bi-directional printing. Networks protocols such as the AppleTalk protocol and Data Link Control (DLC) protocol can provide bi-directional communication in Windows NT. Although TCP/IP can carry the signal, the Line Printer Remote (LPR) specification has no facility for this signal. Therefore, the Windows NT TCP/IP protocol does not support network bi-directional printing.
HPMONOne of the Windows NT Print Monitors, HPMON, supports bi-directional printing over the network. HPMON uses one of its features called "Advanced Job Status" for detecting a response signal sent from the print device. This feature is disabled by default. To enable this feature:
- From the Print Manager Printer menu, choose Properties.
- Choose Settings.
- Choose Port.
- Select the Advanced Job Status check box.
- Quit Print Manager.