[comp.sys.dec] Moving HP Laserjets to Ethernet

dmjd@gauss.uucp (Daniel Devasirvatham 21321) (02/08/91)

We have several HP laserjet printers (+ II & III) which are now running 
off serial links to System V computers.
I am trying to work out a simple way to move them to ethernet.  
They will then be driven by an existing Vax (Ultrix 4) installation
on the ethernet backbone, which already has postscript.  
So, rather than trying to install new hp downloadable fonts etc,
we would like to make these hp laserjets look like postscript printers.

What hardware is available to interface GPIB/HPIB or RS232 to ethernet
(thick lan) ?  This could be either a standalone box or a card that
replaces the current interface card in the laserjets.  Hp makes
a box (expensive) which seems to be tailored to Novell Nets.
Also, would such an interface require special driver software on the
host ultrix computer ?

Hp also makes a postscript cartridge for the laserjet.  
We have the 2 MB memories need to use it.  Will plugging
this in make the hp laserjets look like postscript printers to the outside 
world, or would they still need to be sent special escape sequences etc ?
In short, would we need hp laserjet drivers for ultrix ?

Are there any other alternatives ?

Replies could be sent either to the net (preferable) or the email address below.

Thanks in advance.

Daniel Devasirvatham

dmjd@nyquist.bellcore.com

lrb@alex.ctrg.rri.uwo.ca (Lance R. Bailey) (02/08/91)

In article <1991Feb7.221431.8721@bellcore.bellcore.com> dmjd@nyquist.bellcore.com writes:
>
>We have several HP laserjet printers (+ II & III) which are now running 
>off serial links to System V computers.
>
>What hardware is available to interface GPIB/HPIB or RS232 to ethernet
>
>Hp also makes a postscript cartridge for the laserjet.  
> ....
>In short, would we need hp laserjet drivers for ultrix ?

you have THREE issues here. net access ,PostScript printer from HP lj,
and PostScript printing.

1)  net access. okay, the easiest way to access the printers is to attach them
  via RS232 to a computer which supports remote printing requests. This allows
  _computer_ to handle the spooling, timeouts, paper outs etc.how does the
  'majik network box' handle the paper outs? or even the darn thing powered 
  down.  does it have a disk for spooling requests?  once the printer is
  attached to this computer, then set up remote print queues from other
  computers to it.

    ie: attach the printer to machine A, queue foo. set up machine A to accept
  net requests to print to this computer's queue (sometimes this is the null
  act, sometimes it means playing with hosts.equiv (suns} sometimes the
  printcap entry (VMS running wins/tcp) etc.)  now tell computers B,C, D etc.
  to have queue foo and that queue foo is a remote queue on A.  If B,C,D can
  not remote print, then play games with the rsh command to the A as user lp. I
  can supply details and printer models for the sys5 spooler setup.

    we have ljIII (as PostScript printers), lj2, DEC ln03, applelasers connected
  to VAX/VMS, suns, hp 9/800 and NeXT's and they all are very, very happy
  printing to each other. very transparent, very nice.


    the OTHER method of net access is to buy a printer sharing device and run
  a serial line from each computer to the box and a line from the box to the
  printer.  In this manner I also weave about 8 PC's into the above scheme.

2)  get an HP lj cartridge for the lj III to turn it into a PostScript printer.
  it has at least one subtle bug in it, but this shouldn't annoy you. besides
  right now it is _the_ best for turning an ljIII into a PostScript printer.

    for the other printers, there are a host of cartridges, test-drive the 
  PacificPage and HP models.

2)  PostScript printing. if you turn the HP laser into a PostScript (real:)
  printer then it will act like a PostScript printer.

    Any PostScript printer reads PostScript, and does the following when you
  send it non-PostScript.

    the processing signal (light, sign, dwarve) blinks for a bit and then stops
  with nothing coming out of the printer.

    PostScript is a programming page description language. if 'simple ascii' 
  such as a source listing or a man page is sent to the printer then it chokes.

    The ultrix machine (like the NeXT) generates and sends out PostScript. If
  you tell it to 'print the screen' it generate a PostScript program and THEN
  punts it to the printer. clever.

    Any computer that you wish to have access to the (newly PostScripted) 
  printer must, must, must send PostScript to the printer. If it cannot
  generate PostScript then get get yourself a ascii/hpgl/foo --> PostScript
  interpretor. I've written them, john down the street writes them, the net
  has about a kazillon of them kicking around. take your pick.

welcome to real printing.
-- 
Lance R. Bailey  Systems Manager        box: Robarts Research Institute
          email: lrb@rri.uwo.ca              Clinical Trials Resources Group
            fax: 519.663.3789                P.O. Box 5015, 100 Perth Dr.
            vox: 519.663.3787 ext. 4108      London, Canada N6A 5K8