Xref: utzoo comp.sys.mac:33157 comp.protocols.appletalk:2087
Path: utzoo!attcan!uunet!mcvax!ukc!icdoc!qmc-cs!liam
From: liam@cs.qmc.ac.uk (William Roberts)
Newsgroups: comp.sys.mac,comp.protocols.appletalk
Subject: Re: direct ethernet connected Laserwriters
Summary: not been done yet
Message-ID: <1110@sequent.cs.qmc.ac.uk>
Date: 6 Jun 89 19:11:54 GMT
References: <917@merlin.bhpmrl.oz>
Reply-To: liam@cs.qmc.ac.uk (William Roberts)
Organization: Computer Science Dept, Queen Mary College, University of London, UK.
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In article <917@merlin.bhpmrl.oz> ianh@merlin.bhpmrl.oz (Ian Hoyle) writes:
>Is the speed of printing for the NTX printer governed by how fast the
>print engine can write the postscript image
>(and interpret the postscript file),
>or is there a bottleneck with the speed of the localtalk connection?

It depends. If you ship a 500 byte recursive PostScript program
then the bottleneck is probably in the graphics.

If you ship a bitmap carefully arranged to be monochrome, at
the printer pixel resolution and correctly aligned along the
"grain" of the printer's framebuffer, then LocalTalk is the
bottleneck.


>Has any work been done on directly connecting a Laserwriter to ethernet and
>have it communicate using EtherTalk ??? (is this possible ?? :-)

I asked Glenn Reid this about a month ago and he said "It would
simplify the PostSCript interpreter because it would then be
dealing with only one real-time device, i.e. the laser".
He said they haven't done it, and no-one looked as though they
were trying to hide anything when I mentioned the idea at the
Apple Developer Conference in Sna Jose last month.

I'd like to see such a thing for a lot of reasons:

1) It separates control information from data, so binary images
   work (this isn't possible on the serial line connection)

2) It would cut out the need for LocalTalk, since all our Macs
   have ethernet interfaces

3) It would make it worthwhile for UNIX box vendors to include
   the AppleTalk protocol stack (e.g. the Kinetics
   implementation) as standard. This makes it easy to connect
   these wonderful PostScript printers, plus being easier to
   interwork with Macs, and the whole lot sets itself up with
   minimal administrator intervention.

Come on Apple - how about a LaserWriter NTE?
-- 

William Roberts         ARPA: liam@cs.qmc.ac.uk
Queen Mary College      UUCP: liam@qmc-cs.UUCP    AppleLink: UK0087
190 Mile End Road       Tel:  01-975 5250
LONDON, E1 4NS, UK      Fax:  01-981 7517