Greetings!

> > The few docs I have found on this (501-1910) card call it a "Bi-Pro"
> > for SPARCprinter.  Shall I assume that's technobabble for "special
> > purpose printer interface for SPARCprinter"?
>
> The 501-1910 actually has two things on it: an ordinary bpp (which is
> presumably supported as well, or poorly, as any other bpp is, by the
> bpp driver) and an lpvi (the SPARCprinter interface).  The latter is
> what I recently got a minimal driver working for (which driver Jared
> even more recently made work in a kernel that identifies itself as
> 1.5ZB, which I assume is -current).

OK.  Any clues as to the etymology of "Bi-Pro" (just out
of curiosity/ignorance)?

> > I realize these printers are, ahem, "unique" in their interface
> > characteristics (I assume they are little more than a marking
> > engine?).
>
> Yes, the SPARCprinter itself is little but the print engine.  The host
> interface is little more than a DMA engine and SBus interface.  There

OK.  Looks pretty much like a Versatec flavor interface... i.e. just
pump raw "dots" (video) down the wire, clocking each line in as
a "line sync", etc.  Presumably, your driver builds a bitmap image
of the (desired) printed page in memory and then just ships the
individual "dots" out the interface...?

> are a few registers that must be on the host card because they have to
> work even if the cable is disconnected; probably all the registers the

Understood.

> host sees are there.  I don't know, actually, how the rest is split
> between host card and printer, and I don't really see that it makes
> much difference unless you propose to connect a SPARCprinter to
> something other than an lpvi, or vice versa....

My question is whether there is anything "uniquely desireable" about
having a SPARCprinter -- vs. any of the other existing technologies
or implementations out there.  E.g., aeons ago, Apple Laserwriters
were "uniquely desireable" because they provided native PostScript
support (predating tools like ghjostscript).  A printer that, for example,
could easily handle B size paper has an advantage over other
run-of-the-mill printers, etc.  Sorry, my ignorance is showing... hence the
motivation for the question!  :>

> > Anything else I should consider before hunting around for one (I see
> > them periodically at surplus for a few bucks...)?   Or, am I better
> > served to stick with more "mainstream" printers?
>
> My impression is that coming by the printer and card are comparatively
> easy; the hard part is the cable between the two.  The connector on the
> host end is different from everything else I know of; I suspect it may
> be harder to find in isolation than the whole cable - but if you want,
> I can take an ohmmeter to my SPARCprinter cable and describe the
> pinout.  (The DC pinout, at least - that won't tell me which wires are
> twisted together, or are co-ax, or whatever is inside the jacket.  But
> if you're making your own cable, make it as short as you can get away
> with and such issues are less likely to matter.  My cable's connectors
> look openable, instead of molded on, so I may be able to describe even
> more details - but I haven't tried opening them yet, so....)

Thanks, but I think I saw this cable "lying around" (didn't know what it
was for so didn't pick it up).  Of course, it probably *won't* be there
on  my next visit!  :-/    But, am I still better off sticking with a
"normal"
printer (?)

Thx,
--don