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