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