lvpi is the proprietary SPARCprinter interface--it works with only the
SPARCprinter.  bpp does not work with the SPARCprinter.  It's an added
bonus PeeCee-ish parallel port, in case you have legacy printers laying
around that you want to use, too.

There is no SPARC CPU in the SPARCprinter.  There isn't even any memory in
it.  As you probably aready noticed, laser printers tend to make an image
of the entire page in memory before they start rolling the paper through.
In the SPARCprinter, I believe this image exists either on that 501-1910
card or in the host's main memory--not sure which--but, _not_ in the
printer.

In spite of what a lot of people have been saying, there are tons of these
printers in circulation, and many of them are well-loved by their owners.

The printers are supported under SunOS and maybe Solaris by Ghostscript,
and from what I've read, Ghostscript has a superior rendering engine and
more reliable interface to the device inode compared to NeWSprint, Sun's
for-pay solution.  NeWSprint does not run on newer versions of Solaris.  
Sun's current solution is through a third-party company that also costs
money, but suposedly Ghostscript is good enough.

The idea is _not_ foolish.  These printers, when hooked to an appropriate
CPU or perhaps just using clever spooling, can print _anything_ at rated
speed.  Likewise, this solution allows you to upgrade Postscript rendering
code cleanly and simply, without replacing the whole printer or paying
lots of money to Adobe for poorly supported kludgy backported ROM's.

``Foolish'' is the idea that a $10 wire should limit the printing speed of
a $1500 laser printer.  Since the beginning of time, PeeCee's and Mac's
have had host interfaces too slow to print full page bitmaps at rated
speed.  (Many older printers from that era (like the LJ Series II) were so
broken that they didn't even have enough RAM to hold a full-page bitmap.)
Then the fools work around such a rediculously simple problem by adding
complex lunatic halfass image compression schemes to PCL5.  Or still more
absurd is the idea of paying the extra premium to include a SCSI interface
on your Postscript printer, but instead of connecting the printer to the
host with SCSI, use it to plug the printer into a dedicated hard disk to
cache fonts, and thus avoid downloading fonts over the lame dog of a
host-to-printer interface.

These are not outdated concerns.  My Laserjet 6L on a 450MHz Pentium can't
even do 1ppm when printing full-page Ghostscript-rendered bitmaps.  Of
course it prints at rated speed when used as a WinPrinter, because the
WinDriver makes use of all the silly compression and language kludges.

The NeXT's printer used the lvpi-inspired strategy, too, and was I believe
quite well-regarded.  The NeXT had Display Postscript, so the same code
rendered to the screen and to the printer, and this code was upgraded
along with the OS.  Neither is typically true today.

The SPARCprinter's print engine is made by Xerox.  It's 400dpi.  I believe
it's about 10ppm. AFAIK consumables are still available.  I can dig up a
part number for you if you really care.

The SPARCprinter is probably the fastest, cleverest, beefiest Ghostscript
printing solution you'll find at that price and from that era.  It was
(is) a breath of fresh air in an industry that just doesn't ``get it.''
You're lucky to have it, and shouldn't hold Sun's poor marketing and
failure to provide bug-free software against the printer or the
philosophy. The problem is getting an lvpi driver.  If you solve that
problemm, I want to know right away because I have one, too.  Good luck on
this project.

-- 
Miles Nordin / v:+1 720 841-8308 fax:+1 530 579-8680
555 Bryant Street PMB 182 / Palo Alto, CA 94301-1700 / US