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From: butcher@G.CS.CMU.EDU (Lawrence Butcher)
Newsgroups: comp.laser-printers
Subject: Re: DEC Printserver-40 and Unix machines
Message-ID: <8707151326.AA02261@brillig.umd.edu>
Date: Wed, 8-Jul-87 18:44:11 EDT
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Posted: Wed Jul  8 18:44:11 1987
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I used the SUN Decnet software to snoop the Ethernet packets sent between a
VMS machine and the DEC Printserver 40.  I guessed enough about the protocol
to write a program to spool from the SUN to the printer via LPR.  I did not
discover what happens when there are exceptional conditions in the printer.
The software will not survive changes that DEC makes to the printing protocol.
I do not look inside Postscript files for structuring info.  I wrote this
bare-bones program simply to print my own Postscript documents directly from
the SUN.  I will send this (horrible hack) software to any programmer willing
to improve it.  The program could be converted to run under ULTRIX.

The LPS40 is a complicated and polished product.  It prints at a furious clip.
The printer contains a microvax with lots of memory and no local disk.  DEC
provides VMS software to boot the machine over the Ethernet.  Our LPS40 has
never broken, but I assume that DEC field service would want to download
diagnostics from a VMS machine.  DEC's VMS spooling software gets interesting
messages about printer status back from the LPS40.  Without detailed
documentation of the printing protocol it would be impossible to duplicate
the quality of DEC's supporting software.  Our printer is booted and managed
from a VMS microvax, and most of our users spool thru the VMS machine.

				Lawrence.Butcher@g.cs.cmu.edu

[[Editor's note:  Anyone interested in this should contact
Lawrence.Butcher directly.		--Rick  ]]