PrintServer for USB with 4-Port Switch
Appendix B: About Bi-Directional Printing
Normal printing only sends print signals from a PC to a printer. Bi-directional printing, also called bitronic printing, refers to a printer’s ability to do just the opposite—talk back to a PC to notify it of a print job status, paper jams, etc. This two-way communication technology can be found in HP, IBM, Panasonic, and other laser or color printers where close contact between the PC and printer is key. In color printing, for example, the printer “informs” the PC of its constant status in order to mix color inks correctly for optimal quality output.
Bi-directional communication, communication from a printer to a PC, is normally handled by a combination of the printer hardware and special software on your computer. Bi-directional printers generally have highly advanced parallel interfaces. These printers often require special parallel ports in order to take full advantage of their features.
Using a bi-directional printer on a network poses unique challenges. Unlike a direct PC-to-printer connection in which a bi-directional printer can easily send its signals back to the host PC through the computer’s parallel port (which is normally located only a few feet away from the printer), a networked printer faces the problem of having to route messages bound for a particular PC through a large array of hubs, switches, file servers, and computers. Unfortunately, most printers are not equipped to handle the complexities of printer-to-PC communication across a network. That does not mean that they can’t be used on a network, however.
Linksys designed the PrintServers to function with both regular as well as bi-directional printers. Standard print servers cannot work with bi-directional printers, but the PrintServer features a custom design to support both parallel as well as bi-directional parallel interfaces. However, the PrintServer cannot pass messages from the printer back to the printing PC—this limitation is simply an industry standard, and not one of the PrintServer itself.
However, the PrintServer can check any printer’s online and printing status on the network using the Bi-Admin management utility software packaged with the PrintServer. The status-checking feature built into the management software does not require a bi-directional printer to function. If your printer came with special bi-directional software allowing you to monitor printer status, do not use it with the PrintServer—the software is most likely not network- capable. For best results, turn off the printer’s bi-directional function either by (1) removing any bi-directional printing software from your network computers, and/or (2) turning off the printer’s bi-directional print feature inside of the printer’s on-board menus (if it has menus). Your printer’s user guide should be able to provide specific instructions for doing this.
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