Ghostscript is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY. No author or distributor accepts responsibility to anyone for the consequences of using it or for whether it serves any particular purpose or works at all, unless he says so in writing. Refer to the Ghostscript General Public License for full details.

Everyone is granted permission to copy, modify and redistribute Ghostscript, but only under the conditions described in the Ghostscript General Public License. A copy of this license is supposed to have been given to you along with Ghostscript so you can know your rights and responsibilities. It should be in a file named COPYING. Among other things, the copyright notice and this notice must be preserved on all copies.

For an overview of Ghostscript and a list of the documentation files, see README.

Devices for which this file currently contains documentation:

	SPARCprinter
	HP DeskJet 500C & 550C
	HP PaintJet, XL, and XL300
	DEC LJ250
	Apple Dot Matrix Printer (and Imagewriter)

### ------------------------- The SPARCprinter ------------------------- ###

Introduction

Installation

Afterwards, you can use the following script (the way of handling standard input versus filename-arguments doesn't look very clever, has anyone a better idea ?) to print if you substitute <GSPATH> by the place where you installed the ghostscript binary:

outcmd1='/vol/local/lib/troff2/psxlate -r'
outcmd2='<GSPATH> -I/home/schulte/gs252 -sDEVICE=sparc -sOUTPUTFILE=/dev/lpvi0 -'

if [ $# -eq 0 ]
then
  $outcmd1 | $outcmd2
else
  cat $* | $outcmd1 | $outcmd2
fi

Problems

In case of common printer problems like out of paper, a warning describing the reason will be printed to stdout, the driver will try to access again and again each five seconds.

Due to a problem with the device-driver (in the kernel) the reason of printer failure is not always correctly reported to program. This is the case at least if you open the top cover (Error in the display: E5). Look to the display at the printer if a "Printer problem with unknown reason" is reported.

Fatal errors will cause the print-job to be terminated.

### ------------------------------ End --------------------------------- ###

### ------------------- H-P color inkjet printers ---------------------- ###
###  (DeskJet 500C, DeskJet 550C, PaintJet, PaintJet XL, PaintJet XL300  ###
###  and the DEC LJ250 which can operate in a Paintjet-compatiblme mode) ###

Information and tips on usage for the drivers contained in gdevcdj.c

There are 6 generic drivers contained in the source module:

     1 - cdj500:      HP DeskJet 500C
     2 - cdj550:      HP DeskJet 550C
     3 - pjxl300:     HP PaintJet XL300
     4 - pjtest:      HP PaintJet
     5 - pjxltest:    HP PaintJet XL
     6 - declj250:    DEC LJ250

 All of these drivers have 8-bit (monochrome), 16-bit and 24-bit
     (colour) and for the DJ 550C 32-bit, (colour, cmyk mode)
     options in addition to standard colour and mono drivers.
 It is also possible to set various printer-specific parameters
     from the gs command line, eg.

  gs -sDEVICE=cdeskjet -sBitsPerPixel=16 -dDepletion=1 -dShingling=2 tiger.ps

NB/ The old names cdeskjet, cdjcolor and cdjmono drivers have been retained;
    however, their functionality duplicates that available using the above
    drivers (and cdeskjet is identical to cdj500), ie. we can use:

	gs -sDEVICE=cdj500 -dBitsPerPixel=24 ...	for cdjcolor, and
	gs -sDEVICE=cdj500 -dBitsPerPixel=1  ...	for cdjmono

If the preprocessor symbol A4 is defined, the default paper size is the European A4 size; otherwise it is the U.S. letter size (8.5"x11"). Other paper sizes (including A3 for the PaintJet XL and PaintJet XL300) may be specified on the command line as explained in the Ghostscript documentation.

DEFAULT BITS-PER-PIXEL:

If the preprocessor symbol BITSPERPIXEL is defined as an integer (see below for the range of allowable values), this number will be used to define the default bits-per-pixel (ie. bit depth) for the generic drivers. If the symbol is not defined, the default is set to 24 bits per pixel. It is of course still possible to specify the value from the command line, as described below. Note also that the cdeskjet, cdjcolor and cdjmono drivers are unaffected by setting this symbol, as their default settings are predefined to be 1, 3 and 24 respectively.

DESKJET PHYSICAL LIMITS:

Maximum printing width = 2400 dots = 8". The printer manuals say that the maximum recommended printing height on the page is 10.3", but since this is obviously not true for A4 paper, and I have been unable to detect any problems in printing longer page lengths, this would seem to be a rather artificial restriction.

All Deskjets have 1/2" unprintable bottom margin, due to the mechanical arrangement used to grab the paper. Side margins are approximately 0.25" for US Letter paper, and 0.15" for A4.

COMMAND LINE PARAMETERS:

Several printer 'properties' have been implemented for these printers. Those available so far are all integer quantities, and thus may be specified as eg.

gs -dBitsPerPixel=32 -dShingling-1 ...

BITS-PER-PIXEL:

All of the drivers in gdevcdj.c accept a command line option to set the BitsPerPixel property. This gives considerable flexibility in choosing various trade-offs between speed/quality/colour etc. The valid numbers are:

	1:	This is a standard Ghostscript monochrome driver, and uses
		black ink (by installing the separate mono cartridge in
		the case of the DeskJet 500C, or automatically for the
		other printers)

	3:	A standard Ghostscript colour driver, using internal
		dithering. This is fast to compute and to print, but
		the clustered dithering can lose some detail and
		colour fidelity.

	8:	An 'error-diffusion' monochrome driver which uses
		Floyd-Steinberg dithering to print greyscale images.
		The patterns are much more randomised than with the
		normal clustered dithering, but the data files can
		be much larger and somewhat slower to print.

	16:	This is a 'cheaper' version of the following (24-bit)
		driver, which generates a Floyd-Steinberg colour dithered
		output using the minimum amount of memory (this may be
		helpful when using IBM PC's when Ghostscript has not
		been compiled using a 32-bit 386-style compiler). The
		quality can be almost as good as the 24-bit version.

	24:	A high-quality colour driver using Floyd-Steinberg dithering
		for maximum detail and colour range. However it is very
		memory intensive and thus can be slow to compute (and it
		tends to produce rather larger raw data files, so they
		can also be slower to print).

	32:	This is for the DeskJet 550C only, which uses the black
		cartridge and the colour cartridge simultaneously (ie.
		CMYK printing). This printer can be both faster and give
		higher quality than the DeskJet 500C, because of the
		true black ink. (Note that the 24-bit mode also permits
		CMYK printing on this printer, and uses less memory. Any
		differences between 24-bit and 32-bit should be very small.)

 The addional properties available for the DeskJets are:

        BlackCorrect	(int)	  /* Colour correction to give
				   * better blacks when using the DJ500C
				   * in colour mode, eg. the default of 4
				   * reduces the cyan component to 4/5 
				   * Range accepted: 0 - 9 (0 = none) */
	Shingling	(int)	  /* Interlaced, multi-pass printing 
	                           * 0 = none, 1 = 50%, 2 = 25%, 2 is
				   * best & slowest */
	Depletion	(int)	  /* 'Intelligent' dot-removal 
		                   * 0 = none, 1 = 25%, 2 = 50%, 1 best
				   * for graphics? 
				   * Use 0 for transparencies */

PAINTJET XL300/PAINTJET XL PROPERTIES:

	PrintQuality	(int)	  /* Mechanical print quality
				   * -1 = fast, 0 = normal, 1 = presentation
				   * Fast mode reduces ink usage and uses
				   * single-pass operation for some media
				   * types. Presentation uses more ink and
				   * max number of passes, ie. slowest
				   * printing for highest quality */
	RenderType	(int)	  /* 0 = driver does dithering
				   * 1 = snap to primaries
				   * 2 = snap black -> white, others to black
				   * 3 = ordered dither
				   * 4 = error diffusion
				   * 5 = monochrome ordered dither
				   * 6 = monochrome error diffusion
				   * 7 = cluster ordered dither
				   * 8 = monochrome cluster ordered dither
				   * 9 = user-defined dither (not supported)
				   * 10 = monochrome user-defined dither ns. */

PAINTJET PROPERTIES:


	No additional properties


GAMMA CORRECTION:


 One consequence of using Floyd-Steinberg dithering rather than Ghostscript's
 default clustered ordered dither is that it is much more obvious that the
 ink dots are rather larger on the page than their nominal 1/180" or 1/300"
 size (clustering the dots tends to minimise this effect). Thus it is often
 the case that the printed result is rather too dark. A simple empirical
 correction for this may be achieved by preceding the actual postscript
 file to be printed by a short file which effectively sets the gamma for
 the device, eg.


 gs ... gamma.ps colorpic.ps quit.ps


 where gamma.ps is


%!

{0.333 exp} dup dup currenttransfer setcolortransfer


 This example sets the gamma for r, g, and b to 3, which seems to work
 reasonably well in practice.



GENERAL TIPS:


 For all the above printers, the paper is critically important to the 
 final results. Smoother, less fibrous paper is generally better (and
 suggested types are given in the printer manuals). In particular, the
 special ink-jet paper can make a big difference; the colours are 
 brighter, but most importantly, there is almost no colour bleed, even 
 with adjacent areas of very heavy inking. Similarly, the special coated
 transparencies also work well (and ordinary transparencies do not work
 at all!)


 The unix-lpr.sh provides one example of setting up a multi-option
 colour postscript lpr queue on Unix systems, and includes the ability
 to choose a range of different colour options and printer accounting
 and error logging.



CAVEAT EMPTOR!:


 It is not always easy for me to test all of these drivers, as the only
 colour printer I have here is the DeskJet 500C. I rely on others testing
 drivers for the additional machines and reporting their findings back to
 me. 

### ------------------------------ End --------------------------------- ###

### ------------------- Apple Dot Matrix Printer  ---------------------- ###

This section was written by Mark Wedel.


 The Dot Matrix Driver (DMP) driver is a simple driver I wrote.  It
could more more efficient, but it seems to print the images fine.


 The Dot Matrix Printer was a parallel predecessor to the Imagewriter
printer.  As far as I know, the Imagewriter commands are a superset
to those of the Dot Matrix printer, so the driver should work fine at
generating output that can be printed on Imagewriters.

 A few notes (from the gdevadmp.c file):

 * To print out images, it sets the printer for unidirection printing
 * and 15 cpi (120 dpi). IT sets line feed to 1/9 of an inch (72 dpi).
 * When finished, it sets things back to bidirection print, 1/8" line
 * feeds, and 12 cpi.  There does not appear to be a way to reset
 * things to initial values.
 *
 * This code does not set for 8 bit characters (which is required). It
 * also assumes that carriage return/newline is needed, and not just
 * carriage return.  These are all switch settings on the DMP, and
 * I have configured them for 8 bit data and cr only.
 *
 * You can search for the strings Init and Reset (in devdemp.c) to find the
 * strings that set up the printer and clear things when finished, and change
 * them to meet your needs.
 *
 * Also, you need to make sure that the printer daemon (assuming unix)
 * doesn't change the data as it is being printed.  I have set my
 * printcap file (sunos 4.1.1) with the string:
 * ms=pass8,-opost
 * and it works fine.

 Mark Wedel
master@cats.ucsc.edu

### ------------------------------ End --------------------------------- ###