Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!uunet!mcsun!ukc!icdoc!ih
From: ih@doc.ic.ac.uk (Ian Harries)
Newsgroups: comp.sys.mac
Subject: Re: Imagewriter & Sys 6.0.4
Message-ID: <1599@gould.doc.ic.ac.uk>
Date: 15 Feb 90 13:48:25 GMT
References: <24444@ut-emx.UUCP>
Reply-To: ih@doc.ic.ac.uk (Ian Harries)
Organization: Dept. of Computing, Imperial College, London, UK.
Lines: 74

In article <24444@ut-emx.UUCP> bokonon@walt.cc.utexas.edu (Genghis Khan) writes:
>
> Greetings!
>
>   Please excuse my ignorance if this subject has been breached and solved
>already....
>
>  I work in a lab that has 10 Mac IIs and about 8 Mac Pluses.  The IIs have
>2 MB RAM and the Pluses 2.5.  At the moment, we seem to have fallen victim to
>a bug i'd yet to see, until we started using 6.0.4.  
>
> Basically, when printing to a direct connect Imagewriter, from any Mac, using
>any word processor (i haven't seen the error when using other programs)
>the first page of output will have an integer number at the top, left-hand 
>corner, usually 16,xxx.  The rest of the lines on the page will have double
>"o"s (stacked on top of each other), a pair on either end of each line.
>  The only solution seems to be rebooting the Mac and turning the Imagewriter
>OFF and then ON.
>
> (system details deleted ...)
>
>   Any help will be most gratefully appreciated!
>
>   johan van Zanten
>
>(bokonon@snowwhite.cc.utexas.edu)

You do not say if these are ImageWriter Is or ImageWriter IIs.
We run the CAP software on a Sun 3/280 here at Imperial DoC, including the
ImageWriter spooler. (Side note to Alex Heatley in Wellington - I will be
following up your isrv info request SOON !) The SAME phenomenon occured when
spooling to an ImageWriter I, but not to an ImageWriter II. A look at the
respective manuals provided the answer: The ImageWriter II has a superset of
the ImageWriter I control sequences. These bytes cannot be interpreted by an
ImageWriter I and so are passed on to be printed. Hence the spurious
characters.

e.g. (from my own experience)

     The ImageWriter II has a control sequence 'Set form length' as follows

     ESCAPE H nnnn     27 72 dddd     In increments of nnnn/144

     The ImageWriter I does not have this control sequence, so at the top
     of the first page of output on computer paper, "H1584" would appear
     (11" x 144 dpi).

The same would almost certainly occur with ImageWriter clones, including the
Grappler interface. Strictly, they should be referred to as ImageWriter I
clones.

Interestingly, using a serially-connected ImageWriter I with System Software
6.0.3 ImageWriter driver works fine. It is only the AppleTalk ImageWriter
driver which generates ImageWriter II-specific control sequences. I can imagine
the line of reasoning now - "only ImageWriter IIs can be networked, so we
can use the extra control sequences in the AppleTalk ImageWriter driver.
ImageWriter Is and IIs can both be used with a serial connection, so we must
restrict ourselves to that set of control sequences BOTH can interpret with the
(direct connect) ImageWriter driver".

Not having used system 6.0.4, I do not know if it comes with a newer
ImageWriter driver, but it certainly sounds to me as if the printer is getting
control sequences it cannot cope with.

Of course, I could be completely wrong...

I look forward to hearing about it

  Ian Harries                                   Department of Computing  
  MicroComputer Support Officer                 Imperial College
                                                180 Queen's Gate
  Janet: ih@uk.ac.ic.doc                        London SW7 2BZ
  DARPA: ih%doc.ic.ac.uk                        United Kingdom
  Uucp:  ih@icdoc.UUCP, ukc!icdoc!ih            Tel: +44 1 589 5111 x5052