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I had the use of a Hewlett-Packard LaserJet (HP 2686A) printer for a
few days in November, 1984, and was able to develop a <PLOT79> device
interface for it. The following review was written on 29-Nov-84, and
in February, I took delivery of one for use on my IBM PC. For the
price, this printer has everything else on the market beat, and I have
no hesitation in recommending it. As the review shows, it does have
limitations, but I am otherwise very happy with it.
I have now had about 4 days experience with the HP LaserJet
printer, which uses the Canon LBP-CX print engine, a 300
dot/inch, 8 page/minute device. It has a list price of $3495,
but HP has aggressively discounted it 38% to the University of
Utah, making it available to us for $2167. A recent post-Comdex
issue of PC Week reports that HP expects to reduce the list
price in January to about $2500 and enhance the graphics. HP
confirms that this will include at least a screen-dump facility
for the IBM PC, but not more memory.
The printer comes with a manual of approximately 130 pages,
including a 15-page one-column index. I found it quite clear
and readable. Chapter 2 gives set-up and handling instructions,
plus information on interfacing to an HP 150 and an IBM PC. A
two-character LED display on the control panel shows error codes
which can be looked up in the user's manual, and the most common
ones (paper out, paper jam, etc.) are printed on the panel. I
have experienced only one paper jam, and after clearing it, the
page was automatically reprinted.
The printer functions are a superset of other HP printers and
use the same escape sequences for the same functions. With the
HP 150 personal computer, a program is provided to select
various options as well as to emulate Diablo 630 and HP 2601
printers. HP confirms that this is not available on the printer
itself. We will therefore have to modify our word processors
and document formatters to know about the LaserJet.
The LaserJet has two ROM-resident fonts: portrait and landscape
orientation for fixed-width, 10 characters/inch, 12 point,
Courier medium weight typeface. Other fonts are available on
plug-in cartridges. It is not possible to change cartridges in
mid-page, because the power must be cycled when the cartridge is
removed.
The built-in commands are as follows:
** underlining
** character set choice for primary and secondary fonts
* symbol set
* stroke weight (light, medium, bold)
* pitch
* proportional/fixed spacing
* font style (upright or italic)
* font typeface (line printer, Pica, Elite, Courier,
Helvetica, Times Roman, Gothic, Script, Prestige)
* font height (in fractional points)
** page length, top and left margins (in lines and characters)
** vertical spacing (lines/inch or 1/48inch increments)
** half line feed
** raster graphics
* set resolution (300, 150, 100, or 75 dots/inch; each
raster dot is printed in a 1 x 1, 2 x 2, 3 x 3, or 4 x
4 block for these)
* begin raster graphics
* send raster line (count field followed by 8-bit bytes
defining raster pattern for one horizontal raster
line)
* end raster graphics
** reset and self-test
** horizontal motion index
** cursor positioning (move to row/column, or move to (h,v)
in decipoints) (1 inch = 72.27 points, so 0.1 point is less
than 1/2 dot)
** display functions mode (unfortunately, control characters
print as blanks)
** miscellaneous (select line terminator, line wrap on/off,
portrait/landscape orientation, number of copies, input
feeder control (for page eject or manual insertion of sheet
or envelope))
The manual does not make it entirely clear that the way a page
is ejected is to send the printer a formfeed (ASCII <FF>,
decimal 12). For multipage documents, the printer will
automatically do a page eject according to the current page
length, but a final formfeed is necessary to get the last page
out. It can be forced manually by taking the printer offline
and hitting the formfeed button.
At present, I have two cartridges available, one with Courier
fonts, and one with Helvetica and Times Roman. I was able to
talk to an HP Representative in the LaserJet development
laboratory in Boise, Idaho, who was most helpful. One can also
call the nationwide HP help number: (800) HP-COACH (i.e. (800)
472-6224), but that is in California, and they refer the call to
the folks in Boise.
Baud rate is factory set at 9600 baud; it is possible to change
it, but only by opening up the printer (about six screws need to
be removed) and resetting some DIP switches inside.
Here now are my comments on the LaserJet. By and large, I am
very pleased; this is so very much better than any daisy wheel
printer, and I hope I never again have to print on a daisy wheel
or low-cost dot matrix printer.
The printer has 59K bytes available for graphics. At 300 dpi
this gives a plot 2.3 x 2.3 inches square, but the same bitmap
with the 100 dpi prefix fills a 6.95 x 6.95 inch square, and
with the 75 dpi prefix can more than fill the 8 x 10 inch
printable area on the page. The graph can be positioned
arbitrarily on the page, and subject to the 59K-byte memory
size, several graphs could be printed on the page, although I
have not yet tried this.
The character buffer is 56K bytes; the printer sends XOFF (<DC3>
or <CTL-S>) when the buffer is within 64 characters of full. If
data continues to be received, XOFF is sent again at 32, 16, 8,
and 4 characters from full. After that, a flashing error code
indicates buffer overrun. I hit this problem when I ran the
printer on a standalone host which could not react fast enough
at 9600 baud to stop transmission. I strongly suggest to HP
that the limit at which XOFF is sent should be user-definable;
this becomes even more important when the printer is attached to
a network and the data flow must pass through several computers.
My major source of frustration has been in the choice of fonts.
Instead of being able to choose a specific font listed on the
font cartridge, you specify the parameters noted above (pitch,
style, fontface, etc), and the LaserJet tries to find a ``best
fit''. I spent two hours and about 100 sheets of paper just
trying to get boldface and normal typewriter text out. HP tells
me that a lot of people have complained about this, so I expect
it will get fixed in the near future.
I spent some time trying to format multi-column address label
listing for printing on Xerographic gummed and perforated label
paper. The particular labels I have are 1.5 inches high, 3
columns per page. At 6 lines/inch, 9 lines fit in the 7 labels,
giving 63 lines. Unfortunately, the LaserJet will not print
more than 62 lines per page, unless the interline spacing is
changed, but that would not fit on the perforated labels. I
have therefore resigned myself to 18 labels per sheet instead of
21, giving up the bottom 3.
My last complaint is that ASCII tab characters are discarded.
Since tabs are used heavily in some operating systems,
particularly the DEC and Unix worlds, this makes it necessary to
filter them out before printing the files. I urge HP to make
tabs default to columns 9, 17, ..., 8n+1 as is conventional in
the ASCII world, and optionally, give the user the choice of
setting tab stop positions.
Note added: [21-Oct-85]
The LaserJet made its market entry at $3995, substantially below
any laser printer on the market, and in the last year, has spawned
about a half dozen competitors, most using the same engine. In
September, 1985, the LaserJet Plus was announced at a list price of
$3995, and the price of the regular LaserJet was reduced to $2995.
The LaserJet Plus expands the limited graphics memory of the
LaserJet substantially, though regrettably not to the 945K bytes
required for a full bitmap at 300 dots/inch, and offers
downloadable fonts.