.\" asc(4) - manual page for the scanner device driver `asc' .\" .\" .\" Copyright (c) 1995 Gunther Schadow, Luigi Rizzo. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgements: .\" This product includes software developed by Gunther Schadow. .\" This product includes software developed by Luigi Rizzo. .\" 4. The name of the author may not be used to endorse or promote products .\" derived from this software without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR .\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES .\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. .\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, .\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT .\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, .\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" .\" $FreeBSD: src/share/man/man4/man4.i386/asc.4,v 1.14.2.2 2001/08/17 13:08:45 ru Exp $ .\" $DragonFly: src/share/man/man4/man4.i386/asc.4,v 1.3 2006/02/17 19:37:10 swildner Exp $ .Dd January 19, 1995 .Dt ASC 4 i386 .Os .Sh NAME .Nm asc .Nd device driver for a GI1904-based hand scanner .Sh SYNOPSIS .Cd "device asc0 at isa? port IO_ASC1 drq 3 irq 10" .Sh DESCRIPTION The .Nm character device driver currently handles the .Tn GI1904 Ns -based hand scanner (e.g. Trust Amiscan Grey). It uses DMA and interrupts. Up to 50 lines of scanned input data are buffered in the driver. .Pp The device can operate at four different resolutions: 100, 200, 300 and 400 dots per inch. It produces a simple bitmap with the most significant bit at the left side. The driver can optionally output the simple portable bitmap file format .Xr pbm 5 ; thus the scans can easily processed by most graphics packages. .Pp The width of the output bitmap is fixed as given by the resolution value. However, the height of the bitmap must be supplied when in .Xr pbm 5 mode, since the driver must know at what time the `end-of-file' shall be reached. The default is to produce a square image; i.e., height equals width. With this feature one is able to directly copy the scanner output into a .Xr pbm 5 file using .Xr cat 1 . One can obtain a similar effect by using .Xr dd 1 with the driver in raw mode. .Sh IOCTLS The .Xr ioctl 2 commands applicable to .Nm are listed below. The .Xr sasc 1 provides user-level access to these commands. .Bl -tag -width "ASC_GHEIGHT" .It Dv ASC_GRES .Pq Li int Get current resolution in dots per inch (dpi). .It Dv ASC_GWIDTH .Pq Li int Get current width of the bitmap in pixels. .It Dv ASC_SHEIGHT .Pq Li int Set the height of the bitmap in .Xr pbm 5 mode. This is actually a limit on the amount of lines scannable after the first read operation. When the limit is reached, read will return 0. However, the device is turned off only when the last open file descriptor is closed. .It Dv ASC_GHEIGHT .Pq Li int Get the current height of the bitmap. .It Dv ASC_SBLEN .Pq Li int Set the length of the buffer used internally to do the DMA transfer. The buffer length is supplied in lines of the bitmap. Since the buffer size limit is (currently) 0x3000 bytes, the maximum number of lines allowed will vary with the width of each line. An .Er ENOMEM error is returned if the requested length would exceed this limit. .It Dv ASC_GBLEN .Pq Li int Get the current buffer length in lines. .It Dv ASC_SBTIME .Pq Li int Set the timeout for the completion of reading one buffer. Since a handy scanner is a human/computer interface timeout values are usually higher than those of a flat scanner; the default is 15 seconds. After timeout is reached the read operation will fail with .Er EBUSY . Note that the timeout timer starts anew for each buffer to be read and thus reducing it does not result in faster scans for longer images. .It Dv ASC_GBTIME .Pq Li int Get the current buffer timeout. .El .Pp All .Fn ioctl requests that modify a parameter except .Dv ASC_SBTIME do not have an effect on an ongoing scan process. The user must close the device and open it again for the new selections to take effect. Consequently, the selections are .Em not reset when the device is opened or closed. .Pp Similarly, requests that read a value do not report the value that is used for the ongoing scan process. The values needed during the scan process are saved when it starts and thus are not accessed by .Fn ioctl requests. .Pp The .Dv ASC_SBTIME value does, however, have an immediate effect on the ongoing scan. Thus the timeout can, for example, be set to a large value until the user starts scanning, and then set to a small value to react (nearly) immediately when the user stops. .Pp Note that the .Xr pbm 5 versus raw mode selection is done by the minor number, not by .Fn ioctl requests. In raw mode, the selected height of the bitmap will have no effect. .Sh FILES .Bl -tag -width /dev/asc0pd -compact .It Pa /dev/asc0 device node for raw output .It Pa /dev/asc0d device node for raw output, emitting debug messages if the .Dv ASCDEBUG option was given in the kernel configuration file .It Pa /dev/asc0p device node for output in .Xr pbm 5 file format .It Pa /dev/asc0pd device node for .Xr pbm 5 and debug mode .El .\" .\" .Sh DIAGNOSTICS .\" .Sh SEE ALSO .Xr sasc 1 , .Xr pbm 5 .Sh HISTORY The .Nm driver first appeared in .Fx 2.1 . .Sh AUTHORS The .Nm driver was written by .An Luigi Rizzo . .Sh BUGS Ioctl support is not working yet.