sane-hp(5)               SANE Scanner Access Now Easy               sane-hp(5)



NAME
       sane-hp - SANE backend for HP ScanJet scanners

DESCRIPTION
       The sane-hp library implements a SANE (Scanner Access Now Easy) backend
       that provides access to HP ScanJet scanners which support SCL (Scanner
       Control Language by HP).  The following scanners are known positively
       to work with this backend:

              Model:         Product id:     Interface:
              ----------     -----------     ----------
              ScanJet Plus   C9195A          HP Parallel Interface Card
              ScanJet IIc    C1750A 3226     SCSI
              ScanJet IIcx   C2500A 3332     SCSI
              ScanJet IIp    C1790A          SCSI
              ScanJet 3C     C2520A 3503     SCSI
              ScanJet 3P     C2570A 3406     SCSI
              ScanJet 4C     C2520A          SCSI
              ScanJet 4P     C1130A 3540     SCSI
              ScanJet 4100C  C6290A          USB
              ScanJet 5P     C5110A          SCSI
              ScanJet 5100C  C5190A          parallel port
              ScanJet 5200C  C7190A 3846     parallel port/USB
              ScanJet 6100C  C2520A 3644     SCSI
              ScanJet 6200C  C6270A 3828     SCSI/USB
              ScanJet 6250C  C6270A 3828     SCSI/USB
              ScanJet 6300C  C7670A          SCSI/USB
              ScanJet 6350C  C7670A          SCSI/USB
              ScanJet 6390C  C7670A          SCSI/USB
              PhotoSmart     C5100A R029,R030,R032    SCSI

       Support for models 5100C/5200C connected to the parallel port requires
       the ppSCSI driver available at
       http://cyberelk.net/tim/parport/ppscsi.html and http://penguin-
       breeder.org/kernel/download/.


       Support for models 5200C/62X0C/63X0C connected to the USB require the
       kernel scanner driver or libusb. See sane-usb(5) for more details.

       The "hp" backend no longer supports OfficeJet multi-function
       peripherals.  For these devices use the external "hpoj" backend in
       version 0.90 and later of the "HP OfficeJet Linux driver", available at
       http://hpoj.sourceforge.net

       Because Hewlett-Packard does no longer produce scanners that support
       SCL (beside the OfficeJets), the above list of supported scanners is
       complete.  Other HP scanners are not supported by the "hp" backend, but
       might be supported by another one. See http://www.sane-project.org/.
       You can also watch the sane-devel mailing list at
       http://www.sane-project.org/mailing-lists.html.

       More details about the hp backend can be found on its homepage
       http://www.kirchgessner.net/sane.html.

DEVICE NAMES
       This backend expects device names of the form:

              special

       Where special is the UNIX path-name for the special device that
       corresponds to the scanner.  For SCSI scanners the special device name
       must be a generic SCSI device or a symlink to such a device.  Under
       Linux, such a device name could be /dev/sga or /dev/sg2, for example.
       If the special device name contains "usb", "uscanner" or "ugen", it is
       assumed that the scanner is connected by USB.  For the HP ScanJet Plus
       the special device name must be the device that corresponds to the
       parallel interface card that was shipped with the scanner. That is
       /dev/hpscan.  A special driver is required for this card.  See
       ftp://rvs.ctrl-c.liu.se/pub/wingel/hpscan for details. If the link does
       not work, try ftp://sunsite.unc.edu/pub/Linux/kernel/patches/scanners.

CONFIGURATION
       The contents of the hp.conf file is a list of options and device names
       that correspond to HP ScanJet scanners.  Empty lines and lines starting
       with a hash mark (#) are ignored. See sane-scsi(5) and sane-usb(5) on
       details of what constitutes a valid device name.

       Options specified in front of the first line that contains a device
       name are defaults for all devices. Options specified below a line that
       contains a device name apply just to the most recently mentioned
       device.

       Supported options are connect-scsi, connect-device,
       enable-image-buffering, and dumb-read.

       Option connect-scsi specifies that the scanner is connected to the
       system by SCSI.  Input/output is performed using SCSI-commands. This is
       the default.  But if your SCSI device name contains "usb", "uscanner"
       or "ugen", option connect-scsi must be specified. Otherwise it is
       assumed that the scanner is connected by USB.

       Option connect-device specifies that the scanner is connected to the
       system by a special device. Input/output is performed by
       read()/write()-operations on the device. This option must be used for
       HP ScanJet Plus or scanners connected to USB which are accessed through
       a named device (e.g. /dev/usb/scanner0).  For device names that contain
       "usb", "uscanner" or "ugen", it is not necessary to specify option
       connect-device.

       Option enable-image-buffering stores the scanned image in memory before
       passing it to the frontend. Could be used in case of forward/backward
       moving scanner lamp.

       Option dumb-read can be used to work around problems with "Error during
       device I/O". These problems may occur with certain SCSI-to-USB
       converters or Buslogic SCSI cards.  The option should not be used for
       SCSI devices which are working correctly.  Otherwise startup of
       frontends and changing parameters might be slower.

       A sample configuration file is shown below:

              /dev/scanner
              # this is a comment
              /dev/hpscan
                option connect-device

       /dev/scanner is typically a symlink to the actual SCSI scanner device.

FILES
       /etc/sane.d/hp.conf
              The backend configuration file (see also description of
              SANE_CONFIG_DIR below).

       /usr/local/lib/sane/libsane-hp.a
              The static library implementing this backend.

       /usr/local/lib/sane/libsane-hp.so
              The shared library implementing this backend (present on systems
              that support dynamic loading).

       $HOME/.sane/calib-hp:<device>.dat
              Calibration data for HP PhotoSmart PhotoScanner that is
              retrieved from the scanner after calibration. The data is
              uploaded to the scanner at start of the backend if it is in
              media mode 'print media' or if the media mode is changed to
              'print media'.

ENVIRONMENT
       SANE_CONFIG_DIR
              This environment variable specifies the list of directories that
              may contain the configuration file.  Under UNIX, the directories
              are separated by a colon (`:'), under OS/2, they are separated
              by a semi-colon (`;').  If this variable is not set, the
              configuration file is searched in two default directories:
              first, the current working directory (".") and then in
              /etc/sane.d.  If the value of the environment variable ends with
              the directory separator character, then the default directories
              are searched after the explicitly specified directories.  For
              example, setting SANE_CONFIG_DIR to "/tmp/config:" would result
              in directories "tmp/config", ".", and "/etc/sane.d" being
              searched (in this order).

       SANE_DEBUG_HP
              If the library was compiled with debug support enabled, this
              environment variable controls the debug level for this backend.
              E.g., a value of 128 requests all debug output to be printed.
              Smaller levels reduce verbosity.

       SANE_HOME_HP
              Only used for OS/2 and along with use of HP PhotoSmart
              PhotoScanner.  Must be set to the directory where the directory
              .sane is located.  Is used to save and read the calibration
              file.

       SANE_HP_KEEPOPEN_SCSI

       SANE_HP_KEEPOPEN_USB

       SANE_HP_KEEPOPEN_DEVICE
              For each type of connection (connect-scsi, connect-usb,
              connect-device) it can be specified if the connection to the
              device should be kept open ("1") or not ("0").  Usually the
              connections are closed after an operation is performed.  Keeping
              connection open to SCSI-devices can result in errors during
              device IO when the scanner has not been used for some time. By
              default, USB-connections are kept open. Other connections are
              closed.

       SANE_HP_RDREDO
              Specifies number of retries for read operation before returning
              an EOF error.  Only supported for non-SCSI devices. Default: 1
              retry. Time between retries is 0.1 seconds.


BUGS
       HP PhotoSmart PhotoScanner
              In media mode 'slide' and 'negative', scan resolutions are
              rounded to multiple of 300 dpi. The scanner does not scale the
              data correctly on other resolutions. Some newer models (firmware
              code R030 and later) do not support adjustment of
              contrast/intensity level and tone map.  The backend will
              simulate this by software, but only for gray and 24 bit color.

       Automatic Document Feeder (ADF)
              For use of the ADF with xscanimage(1), first place paper in the
              ADF and then change option scan source to 'ADF'. Press 'change
              document' to load a sheet. Then press 'scan' to start a scan.
              Maybe it is sufficient to press 'scan' without 'change document'
              for repeated scans. The use of the preview window is not
              recommended when working with the ADF.  Setting a window to scan
              from ADF is not supported with xscanimage(1).  Try xsane(1).

       Immediate actions
              Some actions in xscanimage(1) (i.e. unload, select media,
              calibrate) have an immediate effect on the scanner without
              starting a scan.  These options can not be used with scanimage.


TODO
       HP PhotoSmart PhotoScanner
              PhotoScanners with firmware release R030 and up have no firmware
              support for contrast/brightness/gamma table. In the current
              backend this is simulated by software on 24 bits data.
              Simulation on 30 bits should give better results.

       Data widths greater than 8 bits
              Custom gamma table does not work.

       Parallel scanner support
              Beside the ScanJet Plus which came with its own parallel
              interface card, currently only the HP ScanJet 5100C/5200C are
              supported.  These scanners are using an internal parallel-to-
              SCSI converter which is supported by the ppSCSI-driver (see
              above).


SEE ALSO
       sane(7), sane-scsi(5), sane-usb(5)

AUTHOR
       The sane-hp backend was written by Geoffrey T. Dairiki. HP PhotoSmart
       PhotoScanner support by Peter Kirchgessner.



                                  13 Jul 2008                       sane-hp(5)
