Ref: 11640009
Title: Connecting LaserWriters with 1.2.1 and 1.3.1
Date: 8/15/88

Copyright 3Com Corporation, 1991.  All rights reserved.

Finally, here's the full compatibility story:

LaserWriter ver. 3+1.2.1   3+1.3.1
================ =======     =======
LaserWriter         x          x
3Plus               x          x
SC                 no(1)      no(1)
NT                  x          x
NTX                 x          x

(1) The LaserWriter SC can only be used when directly connected to
a Macintosh; it cannot be shared on a network.

If you are having problems getting a LaserWriter to work with
3+Print, make sure the serial cable matches the specifications
in the documentation exactly!


Background:

The 3+ spooler replaces the LaserWriter driver file on the
Macintosh with the 3+Print file.  The 3+Print file includes the
LaserWriter driver plus the ability to communicate with 3+ printer
drivers.

The LaserWriter prep file that normally resides on the Macintosh
is replaced by a LaserWriter prep file that resides on the server.
The server file is the same as on the Macintosh, except that it
has been converted into a PC file format for use by the server.
The 3+Print spooler automatically downloads the prep file to the
LaserWriter, working independently of any Apple printing software
that may be on the Macintosh.

There are a few exceptions to this model, including applications
that download a special version of the PostScript prep file (or
dictionary) for the printer.  PageMaker works because it allows
selectable downloading of the special Aldus prep file (either
temporary or permanent).  With 3+Print, you would use the
temporary downloading mode, and thus download with each print job
a copy of Aldus prep to the printer via the spooler.

Note:  The printer may crash from applications that permanently
download special versions of the prep file!  Permanent downloading
means that the prep file is loaded into the printer's random
access memory (RAM) and stays there even after the print job
completes.  With temporary downloading, the special version of the
prep file deletes itself from memory after the print job
completes.  If multiple print jobs are sent to the printer with
permanently downloaded prep files, the printer's RAM quickly fills
up.  The printer then crashes, and has to be rebooted to resume
operating.  Thus, whenever applications are used that download
special versions of the prep file, such as PageMaker, they should
always be used in temporary downloading mode.
