Re: Fwd: Interactive postscript from HP printer...
[email protected] (Perry Hutchison)
| Newsgroups | gmane.comp.printing.ghostscript.devel |
|---|---|
| Message-ID | <558d0215.hsqG+T5eJvVSpjwb%[email protected]> |
Ken Sharp <[email protected]> wrote: > (bear in mind that early PostScript printers used > a uni-directional parallel printer interface). I'm sure _some_ early PostScript printers used the old-style unidirectional parallel interface, but the earliest PostScript printer I ever dealt with -- an Apple LaserWriter -- had serial and Appletalk interfaces (and no parallel interface). The serial interface was definitely bidirectional; I never used the Appletalk capability but it was reputed to also support bidirectional communication. > While it is possible with some printers I can attest from painful > personal experience that in general you get nothing back from a > printer. I would claim that a printer which lacks bidirectional communication capability cannot fully implement the PostScript language, since several PostScript operators -- such as print and pstack -- cannot perform their defined functions without a bidirectional interface.