Conference 7.286::macintosh

Note 954.0 by brodhcp2-90.bro.dec.com::Cornelis "Roger - OMS Brussels-856-7612"
        -< Printing binary PostScript through a Windows NT server? >-
    
    
    Hi,

    I have a Windows NT V4.0 server with two PostScript printers connected
    via parallel ports, used by  (a.o.) a Macintosh.  If I print from the
    Macintosh, selecting ASCII PostScript, everything works as  expected. 
    But if I select binary PostScript, nothing comes out of the printers. 
    The printers are an  HP 4M Plus and a Lexmark 4079 plus, but both
    behave identically with respect to the ASCII/binary  issue.

    If I have the Mac itself generate the PostScript, it is not such a
    problem, as I can easily select ASCII  format.  But often, I get binary
    PostScript files, usually even included EPS files, from "outside", and 
    those I cannot change.

    My question is:  Is there a way I can print binary PostScript from the
    Mac through the Windows NT  server?  And if not, is there a utility
    that allows to easily convert a bunch of (E)PS files from binary  to
    ASCII format?

    Thanks,

    Roger

    

RE:  Note 954.0 by brodhcp2-90.bro.dec.com::Cornelis "Roger - OMS Brussels-856-7612"
        -< Printing binary PostScript through a Windows NT server? >-

>    My question is:  Is there a way I can print binary PostScript from the
>    Mac through the Windows NT  server?

    Yes, there is nothing in the Windows NT server that prohibits
    the printing if binary data. Your problem is the parallel
    connection to the printers. This is most easily fixed by
    setting up a network connection to the printers. HP has
    Jet-direct card that will do the trick. You might need a
    EtherTalk to LocalTalk adapter box for the Lexmark.

>    And if not, is there a utility
>    that allows to easily convert a bunch of (E)PS files from binary  to
>    ASCII format?

    We did the following once for Level 2 Printers: We converted
    the binary PostScript to an ASCII85 stream and setup an
    ASCII Decode filter at the the front of the PostScript.
    This works great on those binary Photoshop EPSF files.
    
    This was implemented for Windoze 3.1 downloading program.
    If you want to implement a standalone converter, I might
    be able to dig up the code for converting binary to
    ASCII85. The terminating conditions for ASCII85 filter
    are a bit tricky.

    Regards,
    Bob Anderson

Bob,

>    Yes, there is nothing in the Windows NT server that prohibits
>    the printing if binary data. Your problem is the parallel
>    connection to the printers. This is most easily fixed by
>    setting up a network connection to the printers. HP has
>    Jet-direct card that will do the trick. You might need a
>    EtherTalk to LocalTalk adapter box for the Lexmark.

Hmm.  I already was afraid of that.

One more question: The HP's PPD file mentions TBCP (Tagged Binary Communications 
Protocol).  Why would it still not print if I
1. On the Mac, print to a file in binary format,
2. Prefix the file with ^AM, and
3. Copy the file to the Windows NT printer port?
Would the appropriate characters inside the file not even be quoted with a ^A?
FWIW, the mechanism of printing to a file in ASCII format, and then copying to 
the Windows NT printer port works fine.

>    We did the following once for Level 2 Printers: We converted
>    the binary PostScript to an ASCII85 stream and setup an
>    ASCII Decode filter at the the front of the PostScript.
>    This works great on those binary Photoshop EPSF files.
>    
>    This was implemented for Windoze 3.1 downloading program.
>    If you want to implement a standalone converter, I might
>    be able to dig up the code for converting binary to
>    ASCII85. The terminating conditions for ASCII85 filter
>    are a bit tricky.

Can you please elaborate a little bit?
Would it be possible to find the code back?

Thanks,

Roger

re: <<< Note 954.3 by brodhcp2-90.bro.dec.com::Cornelis "Roger - OMS Brussels - 856-7612" >>>

> One more question: The HP's PPD file mentions TBCP (Tagged Binary Communications 
> Protocol).  Why would it still not print if I
> 1. On the Mac, print to a file in binary format,
> 2. Prefix the file with ^AM, and
> 3. Copy the file to the Windows NT printer port?

    We wasted a month of development time playing with TBCP.
    It is documented in an Adobe Tech Note called Binary
    Communications Protocol. This tech note documents two
    different flavors of binary communications. The problem with
    BCP and TBCP is they are extremely device dependent.
    Also, you cannot tell what flavor a printer will support
    except through the PPD file.

    On the other hand, ASCII85 is supported by all Level 2
    PostScript printers. Implementing the converter is not
    that complex and will give you a robust solution.
    
> Can you please elaborate a little bit?
> Would it be possible to find the code back?

    You need to write the conversion program in C. I can
    supply you with a module that does binary to ASCII85
    conversion. This will save you a little time since
    the terminating coditions for ASCII85 are tricky.

    /Bob