28 May
1999
28 May
'99
12:19 p.m.
In message <m10nXGL-000IyHC@p850ug1>, Tony Duell writes:
A couple of other data points are worth pointing out here. The
NeXT printer worked this way. Since the display was driven by
translating Display PostScript into a raster pixmap, translating
it to a raster for the printer fit nicely into the model. Sun
also did the raster interface thing with the first SPARCPrinter
(though it's not quite classic by the 10 year rule AFAIK.) These
two are also the only two I can think of off the top of my head
that operate at 400dpi. The default behavior for the SPARCPrinter
was 300dpi, but you could put it into a 400dpi mode. In fact
I had to return a replacement unit becaue it worked fine at 300
but had an amusing wavey right margin at 400dpi.
Brian L. Stuart
At 04:57 PM 5/28/99 -0700, don wrote:
As an aside, there have been laser printer interfaces where the host
computer gets to control the laser engine control signals directly,
rather than talking to a 'formatter board' that turns
text/graphics/postscript/whatever into a suitable bitmap for printing.
Of course this is a slightly higher level than talking to the mechanics
directly, since you have a signal to tell the printer to start a page
rather than having to control the motor and clutches directly. But still,
the host computer has to monitor the Beam Detect signal and send suitably
timed pixels to the laser control input.
The standard PERQ laser printer interface was like this, and I've seen
similar interface cards for PCs, Atari STs and Acorn Archimedes machines On Fri, 28 May 1999, Arlen Michaels wrote:
> Imagine if you had to drive a dot-matrix print head with raw pin-driver
> signals instead of the printer hardware figuring it out for you : same
kind
>> of problem.