gs-pcl3.1

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The possibilities are:
.PP
.RS
.TS
tab();
l l.
DeskJet ModelColour Models
_
T{
DeskJet, DeskJet Plus, DeskJet Portable, 500, 510, 520
T}Gray
310, 320, 340, 400, 500C, 540, 600Gray, CMY
550C, 560CGray, CMY, CMY+K
T{
660C, 670C, 680C, 690C, 850C, 855C, 870C, 890C, 1120C
T}all
.TE
.RE

The subdevices \fBunspecold\fP and
\fBunspec\fP also permit all colour models\&.
A printer capable only of CMY might accept CMY+K or CMYK data,
remapping them to CMY,
and a printer capable of CMY+K might remap CMY data to CMY+K\&.
.PP
The colour model CMY+K is not useful if you have a CMYK printer\&.
In contrast,
if you have a CMY+K or CMYK printer and the two cartridges support different
resolutions,
the colour models Gray or CMY become interesting as well\&.
In most of these cases
the black cartridge can print at a higher resolution than the CMY cartridge,
although the converse does also occur\&.
In addition, ghostscript is generally fastest for Gray\&.
.PP
PCL\ 3+ also supports the colour model RGB
although Hewlett-Packard discourages its use\&.
For this model the printer internally converts the RGB data it receives into
CMY data for printing\&.
Note that not everything which can be demanded when using a CMY palette
in PCL\ 3+ is also permitted when using RGB\&.
Because of its limited usefulness,
\fBpcl3\fP accepts the colour model RGB only for the subdevices
\fBunspecold\fP and \fBunspec\fP\&.
.SS "Media Sizes and Orientations"
.PP
A PostScript document describes its visible content with respect to
a coordinate system called \fIdefault user space\fR\&.
Almost all PostScript devices are \fIpage devices\fR which
paint only a restricted rectangular area in default user space\&.
Part of the state of a page device is therefore the current
\fIpage size\fR,
two numbers specifying the width and height of the sheet to be printed on\&.
These values must be interpreted from default user space,
hence the page size not only describes the
"sheet size" (extension irrespective of orientation) but also the
orientation between page contents and sheet
(portrait if width \(<= height, landscape otherwise)\&.
The page size is requested by the user or the document,
and it is one of the jobs of the device to satisfy this request\&.
.PP
Ghostscript looks at several sources to determine the page size:
.IP "   \(bu" 6
the default size configured for \fBgs\fP
(usually US Letter or ISO A4 in portrait orientation),
.IP "   \(bu" 6
the value given to the option \fBPAPERSIZE\fP in the
invocation,
.IP "   \(bu" 6
the size requested by the document, unless you specify
\fB-dFIXEDMEDIA\fP\&.
.PP
The last applicable item in this list overrides the others,
hence the current page size can change at runtime\&.
.PP
The \fBpcl3\fP driver splits the page size into sheet size and
page orientation and passes the sheet size to the printer\&.
This works only if the printer accepts this size
(accepted sizes are listed in your printer\&'s manual)\&.
For the explicitly supported printers,
the driver knows which sizes are accepted
and will refuse to print if an unsupported one is requested\&.
(If you suspect that \fBpcl3\fP is in error concerning what is
supported,
check the list of supported sizes in the PPD file for the subdevice you are
using\&.)
Group-3 printers also accept a \fIcustom page size\fR command
which permits printing on arbitrarily-sized media
but only within certain limits which are also known to the driver\&.
Unlike the sheet size the page orientation is irrelevant for deciding whether
a particular page size is supported or not\&.
The driver will adapt itself as required by the
PostScript language and rotate the output if necessary\&.
(I know of only one other ghostscript driver capable of this\&.)
.PP
In setting up the PostScript default user space,
\fBpcl3\fP
does not treat envelope sizes differently from other sizes\&.
.PP
The subdevice \fBunspecold\fP accepts all sizes supported by
the HP DeskJet 560C,
\fBunspec\fP supports all discrete sizes known to the
HP DeskJets 850C/855C/870C/890C and
treats in addition every other size request as a custom page size
without imposing any limits\&.
If using any of these two subdevices you should change the list of supported
sizes to fit your printer\&'s capabilities;
see the
\fI\fICONFIGURATION\fP\fR
section below for details\&.
.PP
In order for a document to be printed correctly
a sheet of appropriate size must be provided and the driver must know
what its orientation with respect to the printing mechanism is\&.
The latter is usually specified by reference to the feeding direction as
"short edge first" or "long edge first"\&.
Don\&'t confuse this kind of orientation with the portrait/landscape
orientation:
the former ("sheet orientation") refers to the orientation of the sheet
with respect to the feeding direction,
the latter ("page orientation") describes the orientation of the sheet with
respect to the page contents (default user space)\&.
These orientations are logically independent:
people inserting paper into the printer need to know about the first,
people composing documents only care about the latter\&.
.PP
Because \fBpcl3\fP
has no information about the actual dimension or orientation of the medium
in the input tray,
you must ensure yourself that this is appropriate\&.
By default, the driver assumes the dimension to be that requested via the
page size,
but you can override this assumption with an \fBInputAttributes\fP
definition (see the
\fI\fIMedia Sources and Destinations\fP\fR
subsection in the \fICONFIGURATION\fP section below)\&.
.PP
There is no command in PCL\ 3+ to tell the printer about the
sheet\&'s orientation in the input tray,
therefore it cannot be chosen and the manufacturer must prescribe it\&.
I am not aware of any precise and complete statement from Hewlett-Packard
about what is required in this respect,
hence you should check your printer\&'s manual whether the assumptions made by
\fBpcl3\fP are correct or not:
the driver assumes that media are always fed short edge first except when
using the subdevices
\fBhpdj\fP,
\fBhpdjplus\fP,
\fBhpdj400\fP,
\fBhpdj500\fP
or
\fBhpdj500c\fP
for printing on envelope sizes
(US no\&. 10 and ISO DL)\&.
In these cases you should insert the medium long edge first\&.
If you find that \fBpcl3\fP\&'s default behaviour is incorrect,
you can override it with the option \fBLeadingEdge\fP
or a media configuration file
(see the
\fI\fICONFIGURATION\fP\fR
section below)\&.
.SS "Print Quality and Media Properties"
.PP
With the introduction of the DeskJet 540, HP added two new PCL commands to the
language: "Print Quality" and "Media Type"\&.
For older DeskJets (groups 1 and 2), similar effects can be
achieved by specifying some technical aspects of the printing process in detail\&.
.PP
You can use the \fBPrintQuality\fP and
\fBMedium\fP options to adapt the driver to the desired
output quality and those properties of the medium it must know about,
independent of which kind of subdevice you select\&.
If it corresponds to a printer understanding the new commands,
the option values are passed through to the printer,
otherwise these specifications are
mapped to the older Depletion, Shingling, and Raster Graphics Quality commands
based on recommendations from HP\&.
If you are not satisfied with the result in the latter case,
use the options \fBDepletion\fP,
\fBShingling\fP and
\fBRasterGraphicsQuality\fP
to explicitly set these values\&.
.SS "Diagnostic Messages"
.PP
Error messages issued by this driver start with
"\f(CW? \fIcomponent\fP:\fR"
and warnings with
"\f(CW?-W \fIcomponent\fP:\fR"\&.
The \fIcomponent\fP can be
\f(CWeprn\fR,
\f(CWpcl3\fR, or
\f(CWpclgen\fR,
corresponding to the driver\&'s three internal layers:
the \fBeprn\fP device extends ghostscript without knowing PCL,
\fBpclgen\fP is a module generating PCL without being aware of
ghostscript,
and \fBpcl3\fP is the driver proper connecting the other two
layers\&.
.PP
All these messages are written on the standard error stream\&.
.SH "OPTIONS"
.PP
When specifying options for \fBgs\fP you should keep in mind
that
case is significant,
that some options must be passed as strings (\fB-s\fP)
and others as general tokens (\fB-d\fP),
and that \fBgs\fP
effectively ignores every option it does not recognize\&.
Hence some care in spelling parameter names is necessary\&.
.PP
If you are confused by the large number of options, don\&'t worry\&.
Just ignore those you don\&'t understand and
concentrate first on the following ones,
given here in the order of their importance:
\fB-sDEVICE\fP,
\fB-sSubdevice\fP,
\fB-sColourModel\fP,
\fB-r\fP,
\fB-sPrintQuality\fP,
and
\fB-sMedium\fP\&.
You should also check whether there is an entry in the
\fBreports\&.txt\fP file
in the \fBpcl3\fP distribution
listing working option combinations for your printer\&.
.SS "Standard Options"
.PP
When calling \fBgs\fP with the \fBpcl3\fP driver 
you can specify any option defined for ghostscript\&'s
\fBprn\fP
(printer) device although some have particular meanings or restrictions\&.
This includes all device-independent options described in
\fBgs\fP\fB(1)\fP\&.
You should also look into ghostscript\&'s extended documentation
(file \fI\fBUse\&.htm\fP (link to URL Use.htm) \fR and the section
\fI\fIDevice
parameters\fP (link to URL Language.htm#Device_parameters) \fR
in \fBLanguage\&.htm\fP)\&.
.IP "\fB-sDEVICE=pcl3\fP" 10
This specification selects the \fBpcl3\fP
driver,
but this is not the only way to select it with this option\&.
See the description of the \fBSubdevice\fP option below for other
possibilities\&.
.IP "\fB-dDuplex[=\fIboolean\fP]\fP or \fB-dDuplex=null\fP" 10
This parameter requests duplex printing and can be set to
\fBtrue\fP only for \fBunspec\fP and
\fBunspecold\fP,
and when the
\fBDuplexCapability\fP value is not \fBnone\fP\&.
The default is \fBnull\fP
which for this driver means that the printer\&'s default setting will be used\&.
.IP "" 10
If your printer does not support duplex printing you can achieve the same
effect manually by printing the odd and even pages separately
(use a command like \fBpsselect\fP\fB(1)\fP from the psutils package for extracting these parts)
and reinserting the paper in between\&.
.IP "\fB-r \fIresolution\fP\fP" 10
This option specifies the resolution in
pixels per inch (ppi; sometimes also called dots per inch, dpi)\&.
The driver checks whether the subdevice selected accepts the given
resolution unless the subdevice is \fBunspecold\fP or
\fBunspec\fP\&.
Resolutions supported by at least some of the other subdevices
for some of the colour models are 75, 100, 150, 300, 600