Pbmtoppa User Manual(0)

NAME
pbmtoppa - convert PBM image to HP Printer Performance Architecture (PPA)

SYNOPSIS
pbmtoppa [pbm_file [ppa_file]]

DESCRIPTION

This program is part of Netpbm(1) pbmtoppa converts page images in PBM format to Hewlett Packard's PPA (Printer Performance Architecture) format, which is the data stream format expected by some HP 'Windows-only' printers including the HP Deskjet 820C series, the HP DeskJet 720 series, and the HP DeskJet 1000 series.

pbm_file is the file specification of the input file or - for Standard Input. The default is Standard Input.

The input file contains one or more PBM images, with each one being a single page. Each image must have the exact dimensions of a page (at 600 pixels per inch in both directions). Significantly, this is the format that Ghostscript produces.

ppa_file is the file specification of the output file or - for Standard Output. The default is Standard Output.

To print Postscript on an HP PPA printer, just use Ghostscript with the pbmraw (or pbm) device driver.

You can generate a test page for use with this program with pbmpage.

You can also set up a printer filter so you can submit PBM input directly to your print queue. See the documentation for your print spooler for information on how to do that, or look in hp820install.doc for an example lpd print filter for Postscript and text files.

Sometimes, pbmtoppa generates a file which the printer will not print (because pbmtoppa's input is unprintable). When this happens, all three lights blink to signal the error. This is usually because there is material outside of the printer's printable area. To make the file print, increase the margins via pbmtoppa options or a configuration file. See the section on calibration (#calibration) below.

  About PPA

The PPA printer language is a far lower level language than most. When you use a PPA printer, most of the processing that a conventional printer does is done instead on the computer end of the wire. In particular, pbmtoppa has to do 'swath cutting,' and 'sweep formatting,' which other printers do themselves. There is very little intelligence inside a PPA printer; pbmtoppa generates direct controls for the printer's hardware.

The design goal of PPA was to reduce the cost of a printer by exploiting computing resources already present in the computer that requests the printing. CPU power, ROM, and RAM requirements inside the printer are all reduced compared to a conventional printer.

PPA was new in 1997. It was preceded by Hewlett Packard's PCL (Printer Control Language) language. HP manufactured PPA printers for only a few years, and no one else ever did.

OPTIONS

-v version
    printer version (720, 820, or 1000)

-x xoff
    horizontal offset adjustment in 1/600 inches.

-y yoff
    vertical offset adjustment in 1/600 inches.

-t topmarg
    top margin in 1/600 inches (default: 150 = 0.25 inch)

-l leftmarg
    left margin in 1/600 inches (default: 150 = 0.25 inch)

-r rightmarg
    right margin in 1/600 inches (default: 150 = 0.25 inch)

-b botmarg
    bottom margin in 1/600 inches (default: 150 = 0.25 inch)

-s paper
    paper size: us or a4. Default is us.

-d dpi
    Print resolution in dots per inch.

-f cfgfile
    Read parameters from the configuration file named cfgfile. See CONFIGURATION FILES (#configfile)

The offset adjustments you specify with -x and -y accumulate. I.e. if you specify them multiple times, the total offset adjustment is the sum of the adjustments you specify. -x 60 -x 120 is the same as -x 180.

The -v option undoes any preceding -x and -y options, leaving the horizontal and vertical adjustments their default values.

CONFIGURATION FILES

You can use a configuration file to specify parameters rather than use invocation options. pbmtoppa processes the file /etc/pbmtoppa.conf, if it exists, before processing any options. It then processes each configuration file named by a -f option in order, applying the parameters from the configuration file as if they were invocation options used in the place of the -f option.

Configuration files have the following format:
#Comment
key1 value1
key2 value2
[etc.]

Valid keys are version, xoffset, yoffset, topmargin, leftmargin, rightmargin, bottommargin, papersize, or any non-null prefix of these words. Valid values are the same as with the corresponding invocation parameters.

EXAMPLES

Print a test pattern:
pbmpage | pbmppa >/dev/lp1

Print three pages:
cat page1.pbm page2.pbm page3.pbm | pbmppa >/dev/lp1

Print the Postscript file myfile.ps:
gs -sDEVICE=rawpbm -q -dNOPAUSE -r600 \
   -sOutputFile=- myfile.ps ;\
| pbmtoppa | lpr

CALIBRATION

To be able to print successfully and properly, you need to tell pbmtoppa an X and a Y offset appropriate for your printer to use when generating the page. You can specify these offsets with the -x and -y invocation options or with the xoff and yoff parameters in a pbmtoppa configuration file.

To determine the correct offsets, use the pbmpage program.

If while trying to do this calibration, the printer refuses to print a page, but just blinks all three lights, specify large margins (e.g. 600 pixels -- one inch) via pbmpage invocation options while doing the calibration.

For example:
pbmpage | pbmtoppa >/dev/lp1
or
pbmpage | pbmtoppa | lpr -l
(if your printer filter recognizes the '-l' (direct output) parameter).

In the test pattern, the grid is marked off in pixel coordinate numbers. Unfortunately, these coordinates are probably cut off before the edge of the paper. You'll have to use a ruler to estimate the pixel coordinate of the left and top edges of the actual sheet of paper (should be within +/- 300, may be negative; there are 600 pixels per inch).

Add these coordinates to the X and Y offsets by either editing the configuration file or using the -x and -y command-line parameters.

When pbmtoppa is properly calibrated, the center mark should be in the center of the paper. Also, the margins should be able to be as small as 1/4 inch without causing the printer to choke with 'blinking lights syndrome'.

RED HAT LINUX INSTALLATION

RedHat users may find the following tip from Panayotis Vryonis <vrypan@hol.gr> helpful. The same should work for the 820 and 1000, but it hasn't been tested. Also, use the pbmraw GSDriver if you have it; it's faster.

Here is a tip to integrate HP720C support in RedHat's printtool:

Install pbmtoppa. Copy pbmtoppa to /usr/bin.

Edit 'printerdb' (in my system it is found in /usr/lib/rhs/rhs-printfilters ) and append the following lines:

----------------------Cut here-----------------------
StartEntry: DeskJet720C
  GSDriver: pbm
  Description: {HP DeskJet 720C}
  About: { \
        This driver drives the HP DeskJet 720C \
        inkjet printer. \
        It does not support color printing. \
        IMPORTANT! Insert \
           '- | pbm2ppa -' \
        in the 'Extra GS Options ' field.\
      }
  Resolution: {600} {600} {}
EndEntry
----------------------------------------------------

Now you can add an HP720C printer just like any other, using printtool.

SEE ALSO
pbmpage(1) , pstopnm(1) , pbm(5)

This program was derived from pbm2ppa. pbm2ppa is obsolete and has been replaced by pnm2ppa, which does the same things as pbmtoppa except it also works with color and has lots more features. See http://pnm2ppa.sourceforge.net (http://pnm2ppa.sourceforge.net) for more information about the PPA protocol and the separately distributed pnm2ppa program.

The file INSTALL-MORE in the pbmtoppa directory of the Netpbm source code contains detailed instructions on setting up a system to use pbmtoppa to allow convenient printing on HP PPA printers. It was written by Michael Buehlmann.

AUTHOR

Tim Norman. Copyright (C) 1998. Licensed under GNU Public License

Manual page by Bryan Henderson, May 2000.