  Linux Access HOWTO
  Michael De La Rue,  <access-howto@ed.ac.uk>
  v2.11, 28 March 1997

  The Linux Access HOWTO covers the use of adaptive technology with
  Linux, In particular, using adaptive technology to make Linux accessi-
  ble to those who could not use it otherwise.  It also covers areas
  where Linux can be used within more general adaptive technology solu-
  tions.
  ______________________________________________________________________

  Table of Contents






















































  1. Introduction

     1.1 Distribution Policy

  2. Comparing Linux with other Operating Systems

     2.1 General Comparison
     2.2 Availability of Adaptive Technology
     2.3 Inherent Usability

  3. Visually Impaired

     3.1 Seeing the Screen with Low Vision
        3.1.1 SVGATextMode
        3.1.2 X Window System
           3.1.2.1 Different Screen Resolutions
           3.1.2.2 Screen Magnification
           3.1.2.3 Change Screen Font
           3.1.2.4 Cross Hair Cursors etc..
        3.1.3 Audio
        3.1.4 Producing Large Print
           3.1.4.1 LaTeX / TeX
        3.1.5 Outputting Large Text
     3.2 Aids for Those Who Can't Use Visual Output
        3.2.1 Braille Terminals
        3.2.2 Speech Synthesis
        3.2.3 Handling Console Output
        3.2.4 Optical Character Recognition
     3.3 Beginning to Learn Linux
     3.4 Braille Embossing

  4. Hearing Problems

     4.1 Visual Bells

  5. Physical Problems

     5.1 Unable to Use a Mouse/Pointer
        5.1.1 Unable to Use a Keyboard
           5.1.1.1 Other Input Hardware (X Windows System only)
        5.1.2 Controlling Physical Hardware From Linux
     5.2 Speech Recognition
     5.3 Making the Keyboard Behave
        5.3.1 X Window System.
        5.3.2 Getting Rid of Auto Repeat
        5.3.3 Macros / Much input, few key presses
        5.3.4 Sticky Keys

  6. General Programming Issues

     6.1 Try to Make it Easy to Provide Multiple Interfaces
     6.2 Make software configurable.
     6.3 Test the Software on Users.
     6.4 Make Output Distinct
     6.5 Licenses

  7. Other Information

     7.1 Linux Documentation
        7.1.1 The Linux Info Sheet
        7.1.2 The Linux Meta FAQ
        7.1.3 The Linux Software Map
        7.1.4 The Linux HOWTO documents
        7.1.5 The Linux FAQ
     7.2 Mailing Lists
        7.2.1 The Linux Access List
        7.2.2 The Linux Blind List
     7.3 WWW References
     7.4 Suppliers
     7.5 Manufacturers
        7.5.1 Alphavision
           7.5.1.1 Linux Supported Alphavision AT Products
        7.5.2 Blazie Engineering
           7.5.2.1 Blazie AT Products
        7.5.3 Digital Equipment Corporation
           7.5.3.1 Linux Supported DEC AT Products
        7.5.4 Kommunikations-Technik Stolper GmbH
           7.5.4.1 Linux Supported KTG AT Products

  8. Software Packages

     8.1 Emacspeak
     8.2 BRLTTY
     8.3 Screen
     8.4 Rsynth
     8.5 xocr
     8.6 xzoom
     8.7 NFBtrans
        8.7.1 Compiling NFBtrans on Linux
     8.8 UnWindows
        8.8.1 dynamag
        8.8.2 coloreyes
        8.8.3 border
        8.8.4 un-twm

  9. Hardware

     9.1 Braille terminals driven from Screen Memory
        9.1.1 Braillex
        9.1.2 Brailloterm
        9.1.3 Patching the Kernel for Braillex and Brailloterm
     9.2 Software Driven Braille Terminals
        9.2.1 Tieman B.V.
           9.2.1.1 CombiBraille
        9.2.2 Alva B.V.
        9.2.3 Telesensory Systems Inc. displays
           9.2.3.1 Powerbraille
           9.2.3.2 Navigator
        9.2.4 Braille Lite
     9.3 Speech Synthesisers
        9.3.1 DECTalk Express
        9.3.2 Accent SA
        9.3.3 SPO256-AL2 Speak and Spell chip.

  10. Acknowledgements



  ______________________________________________________________________

  1.  Introduction

  The aim of this document is to serve as an introduction to the
  technologies which are available to make Linux usable by people who,
  through some disability would otherwise have problems with it.  In
  other words the target groups of the technologies are, the blind, the
  partially sighted, deaf and the physically disabled.  As any other
  technologies or pieces of information are discovered they will be
  added.



  The information here not just for these people (although that is
  probably the main aim) but also to allow developers of Linux to become
  aware of the difficulties involved here.  Possibly the biggest problem
  is that, right now, very few of the developers of Linux are aware of
  the issues and various simple ways to make life simpler for
  implementors of these systems.  This has, however, changed noticeably
  since the introduction of this document, and at least to a small
  extent because of this document, but also to a large extent due to the
  work of some dedicated developers, many of whom are mentioned in the
  document's Acknowledgements.


  Please send any comments or extra information or offers of assistance
  to <access-howto@ed.ac.uk> This address might become a mailing list in
  future, or be automatically handed over to a future maintainer of the
  HOWTO, so please don't use it for personal email.

  I don't have time to follow developments in all areas.  I probably
  won't even read a mail until I have time to update this document.
  It's still gratefully received.  If a mail is sent to the blind-list
  or the access-list, I will eventually read it and put any useful
  information into the document.  Otherwise, please send a copy of
  anything interesting to the above email address.


  Normal mail can be sent to



       Linux Access HOWTO
       23 Kingsborough Gardens
       Glasgow G12 9NH
       Scotland
       U.K.




  And will gradually make its way round the world to me.  Email will be
  faster by weeks.



  I can be personally contacted using <miked@ed.ac.uk>.  Since I use
  mail filtering on all mail I receive, please use the other address
  except for personal email.  This is most likely to lead to an
  appropriate response.


  1.1.  Distribution Policy


       The ACCESS-HOWTO is copyrighted (c) 1996 Michael De La Rue



       The ACCESS-HOWTO may be distributed, at your choice, under either the
       terms of the GNU Public License version 2 or later or the standard
       Linux Documentation project terms.  These licenses should be available
       from where you got this document.  Please note that since the LDP
       terms don't allow modification (other than translation), modified ver-
       sions can be assumed to be distributed under the GPL.




  2.  Comparing Linux with other Operating Systems

  2.1.  General Comparison

  The best place to find out about this is in such documents as the
  `Linux Info Sheet', `Linux Meta FAQ' and `Linux FAQ' (see ``Linux
  Documentation'').  Major reasons for a visually impaired person to use
  Linux would include it's inbuilt networking which gives full access to
  the Internet.  More generally, users are attracted by the full
  development environment included.  Also, unlike most other modern GUI
  environments, the graphical front end to Linux (X Windows) is clearly
  separated from the underlying environment and there is a complete set
  of modern programs such as World Wide Web browsers and fax software
  which work directly in the non graphical environment.  This opens up
  the way to provide alternative access paths to the systems
  functionality; Emacspeak is a good example.

  For other users, the comparison is probably less favourable and less
  clear.  People with very specific and complex needs will find that the
  full development system included allows properly customised solutions.
  However, much of the software which exists on other systems is only
  just beginning to become available.  More development is being done
  however in almost all directions.


  2.2.  Availability of Adaptive Technology

  There is almost nothing commercial available specifically for Linux.
  There is a noticeable amount of free software which would be helpful
  in adaptation, for example, a free speech synthesiser and some free
  voice control software.  There are also a number of free packages
  which provide good support for certain Braille terminals, for example.


  2.3.  Inherent Usability

  Linux has the vast advantage over Windows that most of it's software
  is command line oriented.  This is now changing and almost everything
  is now available with a graphical front end.  However, because it is
  in origin a programmers operating system, line oriented programs are
  still being written covering almost all new areas of interest.  For
  the physically disabled, this means that it is easy to build custom
  programs to suit their needs.  For the visually impaired, this should
  make use with a speech synthesiser or Braille terminal easy and useful
  for the foreseeable future.


  Linux's multiple virtual consoles system make it practical to use as a
  multi-tasking operating system by a visually impaired person working
  directly through Braille.


  The windowing system used by Linux (X11) comes with many programming
  tools, and should be adaptable.  However, in practice, the adaptive
  programs available up till now have been more primitive than those on
  the Macintosh or Windows.  They are, however, completely free (as
  opposed to hundreds of pounds) and the quality is definitely
  improving.


  In principle it should be possible to put together a complete, usable
  Linux system for a visually impaired person for about $500 (cheap &
  nasty PC + sound card).  This compares with many thousands of dollars
  for other operating systems (screen reader software/ speech
  synthesiser hardware).  I have yet to see this.  I doubt it would work
  in practice because the software speech synthesisers available for
  Linux aren't yet sufficiently good.  For a physically disabled person,
  the limitation will still be the expense of input hardware.


  3.  Visually Impaired

  I'll use two general categories here.  People who are partially
  sighted and need help seeing / deciphering / following the text and
  those who are unable to use any visual interface whatsoever.


  3.1.  Seeing the Screen with Low Vision

  There are many different problems here.  Often magnification can be
  helpful, but that's not the full story.  Sometimes people can't track
  motion, sometimes people can't find the cursor unless it moves.  This
  calls for a range of techniques, the majority of which are only just
  being added to X.


  3.1.1.  SVGATextMode

  This program is useful for improving the visibility of the normal text
  screen that Linux provides.  The normal screen that Linux provides
  shows 80 characters across by 25 vertically.  This can be changed (and
  the quality of those characters improved) using SVGATextMode.  The
  program allows full access to the possible modes of an SVGA graphics
  card.  For example, the text can be made larger so that only 50 by 15
  characters appear on the screen.  There isn't any easy way to zoom in
  on sections of a screen, but you can resize when needed.


  3.1.2.  X Window System

  For people who can see the screen there are a large number of ways of
  improving X.  They don't add up to a coherent set of features yet, but
  if set up correctly could solve many problems.


  3.1.2.1.  Different Screen Resolutions

  The X server can be set up with many different resolutions.  A single
  key press can then change between them allowing difficult to read text
  to be seen.

  In the file /etc/XF86Config, you have an entry in the Screen section
  with a line beginning with modes.  If, for example, you set this to


       Modes       "1280x1024" "1024x768" "800x600" "640x480" "320x240"




  with each mode set up correctly (which requires a reasonably good mon-
  itor for the highest resolution mode), you will be able to have four
  times screen magnification, switching between the different levels
  using

  Ctrl+Alt+Keypad-Plus and Ctrl+Alt+Keypad-Minus


  Moving the mouse around the screen will scroll you to different parts
  of the screen.  For more details on how to set this up you should see
  the documentation which comes with the XFree86 X server.

  3.1.2.2.  Screen Magnification

  There are several known screen magnification programs, xmag which will
  magnify a portion of the screen as much as needed but is very
  primitive.  Another one is xzoom.  Previously I said that there had to
  be something better than xmag, well this is it.  See section
  ``xzoom''.

  Another program which is available is puff.  This is specifically
  oriented towards visually impaired users.  It provides such features
  as a box around the pointer which makes it easier to locate.  Other
  interesting features of puff are that, if correctly set up, it is able
  to select and magnify portions of the screen as they are updated.
  However, there seem to be interacations between xpuff and the window
  manager which could make it difficult to use.  When used with my fvwm
  setup, it didn't respond at all to key presses.  However using twm
  improved the situation.

  The final program which I have seen working is dynamag.  This again
  has some specific advantages such as the ability to select a specific
  area of the screen and monitor it, refreshing the magnified display at
  regular intervals between a few tenths of a second at twenty seconds.
  dynamag is part of the UnWindows distribution.  See ``UnWindows'' for
  more details.



  3.1.2.3.  Change Screen Font

  The screen fonts all properly written X software should be changeable.
  You can simply make it big enough for you to read.  This is generally
  accomplished by putting a line the file .Xdefaults which should be in
  your home directory.  By putting the correct lines in this you can
  change the fonts of your programs, for example


  Emacs.font: -sony-fixed-medium-r-normal--16-150-75-75-c-80-iso8859-*



  To see what fonts are available, use the program xfontsel under X.

  There should be some way of changing things at a more fundamental
  level so that everything comes out with a magnified font.  This could
  be done by renaming fonts, and by telling telling font generating
  programs to use a different level of scaling.  If someone gets this to
  work properly, please send me the details of how you did it.


  3.1.2.4.  Cross Hair Cursors etc..

  For people that have problems following cursors there are many things
  which can help;


  o  cross-hair cursors (horizontal and vertical lines from the edge of
     the screen)

  o  flashing cursors (flashes when you press a key)


  No software I know of specifically provides a cross hair cursor.
  puff, mentioned in the previous section does however provide a
  flashing box around the cursor which can make it considerably easier
  to locate.

  For now the best that can be done is to change the cursor bitmap.
  Make a bitmap file as you want it, and another one which is the same
  size, but completely black.  Convert them to the XBM format and run


          xsetroot -cursor cursorfile.xbm black-file.xbm



  actually, if you understand masks, then the black-file doesn't have to
  be completely black, but start with it like that.  The .Xdefaults file
  controls cursors used by actual applications.  For much more
  information, please see the X Big Cursor mini-HOWTO, by Joerg
  Schneider <schneid@ira.uka.de>.


  3.1.3.  Audio

  Provided that the user can hear, audio input can be very useful for
  making a more friendly and communicative computing environment.  For a
  person with low vision, audio clues can be used to help locate the
  pointer (see ``UnWindows'').  For a console mode user using Emacspeak
  (see ``Emacspeak''), the audio icons available will provide very many
  useful facilities.

  Setting up Linux audio is covered in the Linux Sound HOWTO (see
  ``Linux Documentation'').  Once sound is set up, sounds can be played
  with the play command which is included with most versions of Linux.
  This is the way to use my version of UnWindows.


  3.1.4.  Producing Large Print

  Using large print with Linux is quite easy.  There are several
  techniques.


  3.1.4.1.  LaTeX / TeX

  LaTeX is an extremely powerful document preparation system.  It may be
  used to produce large print documents of almost any nature.  Though
  somewhat complicated to learn, many documents are produced using LaTeX
  or the underlying typesetting program, TeX.



  this will produce some reasonably large text



       \font\magnifiedtenrm=cmr10 at 20pt  % setup a big font
       \magnifiedtenrm
       this is some large text
       \bye





  For more details, see the LaTeX book which is available in any
  computer book shop.  There are also a large number of introductions
  available on the internet.




  3.1.5.  Outputting Large Text

  Almost all Linux printing uses postscript, and Linux can drive almost
  any printer using it.  I output large text teaching materials using a
  standard Epson dot matrix printer.

  For users of X, there are various tools available which can produce
  large Text.  These include LyX, and many commercial word processors.


  3.2.  Aids for Those Who Can't Use Visual Output

  For someone who is completely unable to use a normal screen there are
  two alternatives Braille and Speech.  Obviously for people who also
  have hearing loss, speech isn't always useful, so Braille will always
  be important.

  If you can choose, which should you choose?  This is a matter of
  `vigorous' debate.  Speech is rapid to use, reasonably cheap and
  especially good for textual applications (e.g. reading a long document
  like this one).  Problems include needing a quiet environment,
  possibly needing headphones to work without disturbing others and
  avoid being listened in on by them (not available for all speech
  synthesisers).

  Braille is better for applications where precise layout is important
  (e.g. spreadsheets).  Also can be somewhat more convenient if you want
  to check the beginning of a sentence when you get to the end.  Braille
  is, however, much more expensive and slower for reading text.
  Obviously, the more you use Braille, the faster you get.  Grade II
  Braille is difficult to learn, but is almost certainly worth it since
  it is much faster.  This means that if you don't use Braille for a
  fair while you can never discover its full potential and decide for
  yourself. Anyway, enough said on this somewhat controversial topic.

  based on original by James Bowden <jrbowden@bcs.org.uk>


  3.2.1.  Braille Terminals

  Braille terminals are normally a line or two of Braille.  Since these
  are at most 80 characters wide and normally 40 wide, they are somewhat
  limited.  I know of two kinds


  o  Hardware driven Braille terminals.

  o  Software driven Braille terminals.


  The first kind works only when the computer is in text mode and reads
  the screen memory directly. See section ``hardware driven Braille
  terminals''.


  The second kind of Braille terminal is similar, in many ways, to a
  normal terminal screen of the kind Linux supports automatically.
  Unfortunately, they need special software to make them usable.


  There are two packages which help with these.  The first, BRLTTY,
  works with several Braille display types and the authors are keen to
  support more as information becomes available.  Currently BRLTTY
  supports Tieman B.V.'s CombiBraille series, Alva B.V.'s ABT3 series
  and Telesensory Systems Inc.'s PowerBraille and Navigator series
  displays.  The use of Blazie Engineering's Braille Lite as a Braille
  display is discouraged, but support may be renewed on demand.  See
  section ``Software Braille Terminals''.


  The other package I am aware of is Braille Enhanced Screen.  This is
  designed to work on other UNIX systems as well as Linux.  This should
  allow user access to a Braille terminal with many useful features such
  as the ability to run different programs in different `virtual
  terminals' at the same time.


  3.2.2.  Speech Synthesis

  Speech Synthesisers take (normally) ASCII text and convert it into
  actual spoken output.  It is possible to have these implemented as
  either hardware or software.  Unfortunately, the free Linux speech
  synthesisers are, reportedly, not good enough to use as a sole means
  of output.


  Hardware speech synthesisers are the alternative.  The main one that I
  know of that works is DECtalk from Digital, driven by emacspeak.
  However, at this time (March 1997) a driver for the Doubletalk
  synthesiser has been announced.  Using emacspeak full access to all of
  the facilities of Linux is fairly easy.  This includes the normal use
  of the shell, a world wide web browser and many other similar
  features, such as email.  Although, it only acts as a plain text
  reader (similar to IBM's one for the PC) when controling programs it
  doesn't understand, with those that it does, it can provide much more
  sophisticated control.  See section ``Emacspeak'' for more information
  about emacspeak.


  3.2.3.  Handling Console Output

  When it starts up, Linux at present puts all of its messages straight
  to the normal (visual) screen.  This could be changed if anyone with a
  basic level of kernel programming ability wants to do it.  This means
  that it is impossible for most Braille devices to get information
  about what Linux is doing before the operating system is completely
  working.


  It is only at that stage that you can start the program that you need
  for access.  If the BRLTTY program is used and run very early in the
  boot process, then from this stage on the messages on the screen can
  be read.  Most hardware and software will still have to wait until the
  system is completely ready.  This makes administering a Linux system
  difficult, but not impossible for a visually impaired person.  Once
  the system is ready however, you can scroll back by pressing (on the
  default keyboard layout) Shift-PageUP.


  There is one Braille system that can use the console directly, called
  the Braillex.  This is designed to read directly from the screen
  memory.  Unfortunately the normal scrolling of the terminal gets in
  the way of this.  If you are using a Kernel newer than 1.3.75, just
  type linux no-scroll at the LILO prompt or configure LILO to do this
  automatically. If you have an earlier version of Linux, see section
  ``Screen Memory Braille Terminals''


  The other known useful thing to do is to use sounds to say when each
  stage of the boot process has been reached. (T.V. Raman suggestion)


  3.2.4.  Optical Character Recognition

  There is a free Optical Character Recognition (OCR) program for Linux
  called xocr.  In principle, if it is good enough, this program would
  allow visually impaired people to read normal books to some extent
  (accuracy of OCR is never high enough..).  However, according to the
  documentation, this program needs training to recognise the particular
  font that it is going to use and I have no idea how good it is since I
  don't have the hardware to test it.


  3.3.  Beginning to Learn Linux

  Beginning to learn Linux can seem difficult and daunting for someone
  who is either coming from no computing background or from a pure DOS
  background.  Doing the following things may help:


  o  Learn to use Linux (or UNIX) on someone else's system before
     setting up your own.

  o  Initially control Linux from your own known speaking/Braille
     terminal.  If you plan to use speech, you may want to learn emacs
     now.  You can learn it as you go along though.  See below

  o  If you come from an MS-DOS background, read the DOS2Linux Mini
     HOWTO for help with converting (see ``The Linux HOWTO Documents'').

  The Emacspeak HOWTO written by Jim Van Zandt (<jrv@vanzandt.mv.com>)
  covers this in much more detail (see ``The Linux HOWTO Documents'').


  If you are planning to use Emacspeak, you should know that Emacspeak
  does not attempt to teach Emacs, so in this sense, prior knowledge of
  Emacs would always be useful.  This said, you certainly do not need to
  know much about Emacs to start using Emacspeak.  In fact, once
  Emacspeak is installed and running, it provides a fluent interface to
  the rich set of online documentation including the info pages, and
  makes learning what you need a lot easier.

  "In summary: starting to use Emacspeak takes little learning.  Getting
  the full mileage out of Emacs and Emacspeak, especially if you intend
  using it as a replacement for X Windows as I do does involve
  eventually becoming familiar with a lot of the Emacs extensions; but
  this is an incremental process and does not need to be done in a day."
  - T.V.Raman

  One other option which may be interesting are the RNIB training tapes
  which include one covering UNIX.  These can be got from



       RNIB
       Customer Services
       PO Box 173
       Peterborough
       Cambridgeshire PE2 6WS
       Tel: 01345 023153 (probably only works in UK)








  3.4.  Braille Embossing

  Linux should be the perfect platform to drive a Braille embosser from.
  There are many formatting tools which are aimed specifically at the
  fixed width device.  A Braille embosser can just be connected to the
  serial port using the standard Linux printing mechanisms.  For more
  info see the Linux Printing HOWTO.


  There is a free software package which acts as a multi-lingual grade
  two translator available for Linux from the American ``National
  Federation for the Blind''.  This is called NFBtrans.  See section
  ``NFB translator'' for more details.


  4.  Hearing Problems

  For the most part there is little problem using a computer for people
  with hearing problems.  Almost all of the output is visual.  There are
  some situations where sound output is used though.  For these, the
  problem can sometimes be worked round by using visual output instead.


  4.1.  Visual Bells

  By tradition, computers go `beep' when some program sends them a
  special code.  This is generally used to get attention to the program
  and for little else.  Most of the time, it's possible to replace this
  by making the entire screen (or terminal emulator) flash.  How to do
  this is very variable though.



     xterm (under X)
        for xterm, you can either change the setting by pressing the
        middle mouse button while holding down the control key, or by
        putting a line with just `XTerm*visualBell: true' (not the
        quotes of course) in the file .Xdefaults in your home directory.


     the console (otherwise)
        The console is slightly more complex.  Please see Alessandro
        Rubini's Visual Bell mini HOWTO for details on this.  Available
        along with all the other Linux documentation (see section
        ``other Linux documents'').  Mostly the configuration has to be
        done on a per application basis, or by changing the Linux Kernel
        its self.



  5.  Physical Problems

  Many of these problems have to be handled individually.  The needs of
  the individual, the ways that they can generate input and other
  factors vary so much that all that this HOWTO can provide is a general
  set of pointers to useful software and expertise.


  5.1.  Unable to Use a Mouse/Pointer

  Limited mobility can make it difficult to use a mouse.  For some
  people a tracker ball can be a very good solution, but for others the
  only possible input device is a keyboard (or even something which
  simulates a keyboard).  For normal use of Linux this shouldn't be a
  problem (but see the section ``Making the keyboard behave''), but for
  users of X, this may cause major problems under some circumstances.
  Fortunately, the fvwm window manager has been designed for use without
  a pointer and most things can be done using this.  I actually do this
  myself when I lose my mouse (don't ask) or want to just keep typing.
  fvwm is included with all distributions of Linux that I know of.
  Actually using other programs will depend on their ability to accept
  key presses.  Many X programs do this for all functions.  Many don't.
  I sticky mouse keys, which are supposedly present in the current
  release of X should make this easier.


  5.1.1.  Unable to Use a Keyboard

  People who are unable to use a keyboard normally can sometimes use one
  through a headstick or a mouthstick.  This calls for special setup of
  the keyboard.  Please see also the section ``Making the keyboard
  behave''.


  5.1.1.1.  Other Input Hardware (X Windows System only)

  For others, the keyboard cannot be used at all and only pointing
  devices are available.  In this case, no solution is available under
  the standard Linux Console and X will have to be used.  If the X-Input
  extension can be taught to use the device and the correct software for
  converting pointer input to characters can be found (I haven't seen it
  yet) then any pointing should be usable without a keyboard.

  There are a number of devices worth considering for such input such as
  touch screens and eye pointers.  Many of these will need a `device
  driver' written for them.  This is not terribly difficult if the
  documentation is available, but requires someone with good C
  programming skills.  Please see the Linux Kernel Hackers guide and
  other kernel reference materials for more information.  Once this is
  set up, it should be possible to use these devices like a normal
  mouse.


  5.1.2.  Controlling Physical Hardware From Linux

  The main group of interest here are the Linux Lab Project.  Generally,
  much GPIB (a standard interface to scientific equipment, also known as
  the IEEE bus) hardware can be controlled.  This potentially gives much
  potential for very ambitious accessibility projects.  As far as I know
  none have yet been attempted.



  5.2.  Speech Recognition

  Speech recognition is a very powerful tool for enabling computer use.
  There are two recognition systems that I know of for Linux, the first
  is ears which is described as ``recognition is not optimal.  But it is
  fine for playing and will be improved'', the second is AbbotDemo ``A
  speaker independent continuous speech recognition system'' which may
  well be more interesting, though isn't available for commercial use
  without prior arrangement.  See the Linux software map for details
  (see section ``other Linux documents'').


  5.3.  Making the Keyboard Behave

  5.3.1.  X Window System.

  The latest X server which comes with Linux can include many features
  which assist in input.  This includes such features as StickKeys,
  MouseKeys, RepeatKeys, BounceKeys, SlowKeys, and TimeOut.  These allow
  customisation of the keyboard to the needs of the user.  These are
  provided as part of the XKB> extension in versions of X after version
  6.1.  To find out your version and see whether you have the extension
  installed, you can try.


  xdpyinfo -queryExtensions




  5.3.2.  Getting Rid of Auto Repeat

  To turn off key repeat on the Linux console run this command (I think
  it has to be run once per console; a good place to run it would be in
  your login files, .profile or .login in your home directory).


  setterm -repeat off




  To get rid of auto repeat on any X server, you can use the command


  xset -r




  which you could put into the file which get runs when you start using
  X (often .xsession or .xinit under some setups)


  Both of these commands are worth looking at for more ways of changing
  behaviour of the console.


  5.3.3.  Macros / Much input, few key presses

  Often in situations such as this, the biggest problem is speed of
  input.  Here the most important thing to aim for is the most number of
  commands with the fewest key presses.  For users of the shell (bash /
  tcsh) you should look at the manual page, in particular command and
  filename completion (press the tab key and bash tries to guess what
  should come next).  For information on macros which provide sequences
  of commands for just one key press, have a look at the Keystroke
  HOWTO.


  5.3.4.  Sticky Keys

  Sticky keys are a feature that allow someone who can only reliably
  press one button at a time to use a keyboard with all of the various
  modifier keys such as shift and control.  These keys, instead of
  having to be held on at the same time as the other key instead become
  like the caps lock key and stay on while the other key is pressed.
  They may then either switch off or stay on for the next key depending
  on what is needed.  For information about how to set this up please
  see the Linux Keyboard HOWTO, especially section `I can use only one
  finger to type with' (section 15 in the version I have) for more
  information on this.  - Information from Toby Reed.



  6.  General Programming Issues

  Many of the issues worth taking into account are the same when writing
  software which is designed to be helpful for access as when trying to
  follow good design.


  6.1.  Try to Make it Easy to Provide Multiple Interfaces

  If your software is only usable through a graphical interface then it
  can be very hard to make it usable for someone who can't see.  If it's
  only usable through a line oriented interface, then someone who can't
  type will have difficulties.

  Provide keyboard shortcuts as well as the use of the normal X pointer
  (generally the mouse).  You can almost certainly rely on the user
  being able to generate key presses to your application.


  6.2.  Make software configurable.

  If it's easy to change fonts then people will be able to change to one
  they can read.  If the colour scheme can be changed then people who
  are colour blind will be more likely to be able to use it.  If fonts
  can be changed easily then the visually impaired will find your
  software more useful.


  6.3.  Test the Software on Users.

  If you have a number of people use your software, each with different
  access problems then they will be more likely to point up specific
  problems.  Obviously, this won't be practical for everybody, but you
  can always ask for feedback.


  6.4.  Make Output Distinct

  Where possible, make it clear what different parts of your program are
  what.  Format error messages in a specific way to identify them.
  Under X, make sure each pane of your window has a name so that any
  screen reader software can identify it.


  6.5.  Licenses

  Some software for Linux (though none of the key programs) has license
  like `not for commercial use'.  This could be quite bad for a person
  who starts using the software for their personal work and then
  possibly begins to be able to do work they otherwise couldn't with it.
  This could be something which frees them from financial and other
  dependence on others people.  Even if the author of the software is
  willing to make exceptions, it makes the user vulnerable both to
  changes of commercial conditions (some company buys up the rights) and
  to refusal from people they could work for (many companies are overly
  paranoid about licenses).  It is much better to avoid this kind of
  licensing where possible.  Protection from commercial abuse of
  software can be obtained through more specific licenses like the GNU
  Public License or Artistic License where needed.


  7.  Other Information




  7.1.  Linux Documentation

  The Linux documentation is critical to the use of Linux and most of
  the documents mentioned here should be included in recent versions of
  Linux, from any source I know of.

  If you want to get the documentation on the Internet, here are some
  example sites.  These should be mirrored at most of the major FTP
  sites in the world.


  o  ftp.funet.fi (128.214.6.100) : /pub/OS/Linux/doc/

  o  tsx-11.mit.edu (18.172.1.2) : /pub/linux/docs/

  o  sunsite.unc.edu (152.2.22.81) : /pub/Linux/docs/


  7.1.1.  The Linux Info Sheet

  A simple and effective explanation of what Linux is.  This is one of
  the things that you should hand over when you want to explain why you
  want Linux and what it is good for.

  The Linux Info Sheet is available on the World Wide Web from
  <http://sunsite.unc.edu/mdw/HOWTO/INFO-SHEET.html> and other mirrors.



  7.1.2.  The Linux Meta FAQ

  A list of other information resources, much more complete than this
  one.  The meta FAQ is available on the World Wide Web from
  <http://sunsite.unc.edu/mdw/HOWTO/META-FAQ.html> and other mirrors


  7.1.3.  The Linux Software Map

  The list of software available for Linux on the Internet.  Many of the
  packages listed here were found through this.  The LSM is available in
  a searchable form from <http://www.boutell.com/lsm/>.  It is also
  available in a single text file in all of the FTP sites mentioned in
  section ``Linux Documentation''.


  7.1.4.  The Linux HOWTO documents

  The HOWTO documents are the main documentation of Linux.  This Access
  HOWTO is an example of one.

  The home site for the Linux Documentation Project which produces this
  information is  <http://sunsite.unc.edu/mdw/linux.html>.  There are
  also many companies producing these in book form.  Contact a local
  Linux supplier for more details.

  The Linux HOWTO documents will be in the directory HOWTO in all of the
  FTP sites mentioned in section ``Linux Documentation''.


  7.1.5.  The Linux FAQ

  A list of `Frequently Asked Questions' with answers which should solve
  many common questions.  The FAQ list is available from
  <http://www.cl.cam.ac.uk/users/iwj10/linux-faq/> as well as all of the
  FTP sites mentioned in section ``Linux Documentation''.

  7.2.  Mailing Lists

  There are two lists that I know of covering these issues specifically
  for Linux.  There are also others which it is worth researching which
  cover computer use more generally.  Incidentally, if a mail is sent to
  these lists I will read it eventually and include any important
  information in the Access-HOWTO, so you don't need to send me a
  separate copy unless it's urgent in some way.


  7.2.1.  The Linux Access List

  This is a general list covering Linux access issues.  It is designed
  `to service the needs of users and developers of the Linux OS and
  software who are either disabled or want to help make Linux more
  accessible'.  To subscribe send email to
  <majordomo@ssv1.union.utah.edu> and in the BODY (not the subject) of
  the email message put:



       subscribe linux-access <your-email-address>





  7.2.2.  The Linux Blind List

  This is a mailing list covering Linux use for blind users.  There is
  also a list of important and useful software being gathered in the
  list's archive.  To subscribe send mail to <blinux-list-
  request@redhat.com> with the subject: help.  This list is now
  moderated.


  7.3.  WWW References

  The World Wide Web is, by it's nature, very rapidly changing.  If you
  are reading this document in an old version then some of these are
  likely to be out of date.  The original version that I maintain on the
  WWW shouldn't go more than a month or two out of date, so refer to
  that please.

  Linux Documentation is available from
  <http://sunsite.unc.edu/mdw/linux.html>

  Linux Access On the Web <http://www.tardis.ed.ac.uk/~mikedlr/access/>
  with all of the versions of the HOWTO in
  <http://www.tardis.ed.ac.uk/~mikedlr/access/HOWTO/>.  Preferably,
  however, download from one of the main Linux FTP sites.  If I get a
  vast amount of traffic I'll have to close down these pages and move
  them elsewhere.

  The BLINUX Documentation and Development Project
  <http://leb.net/blinux/>.  "The purpose of The BLINUX Documentation
  and Development Project is to serve as a catalyst which will both spur
  and speed the development of software and documentation which will
  enable the blind user to run his or her own Linux workstation."

  Emacspeak WWW page
  <http://cs.cornell.edu/home/raman/emacspeak/emacspeak.html>

  BRLTTY unofficial WWW page
  <http://www.sf.co.kr/t.linux/new/brltty.html>

  Yahoo (one of the most major Internet catalogues)
  <http://www.yahoo.com/Society_and_Culture/Disabilities/Adaptive_Technology/>

  The Linux Lab Project  <http://www.fu-berlin.de/~clausi/>.

  The BLYNX pages: Lynx Support Files Tailored For Blind and Visually
  Handicapped Users  <http://leb.net/blinux/blynx/>.


  7.4.  Suppliers

  This is a UK supplier for the Braillex.


  Alphavision Limited




  7.5.  Manufacturers

  7.5.1.  Alphavision

  I think that they are a manufacturer?  RNIB only lists them as a
  supplier, but others say they make the Braillex.


  Alphavision Ltd
  Seymour House
  Copyground Lane
  High Wycombe
  Bucks HP12 3HE
  England
  U.K.



     Phone
        +44 1494-530 555


  7.5.1.1.  Linux Supported Alphavision AT Products


  o  Braillex


  7.5.2.  Blazie Engineering

  The Braille Lite was supported in the original version of BRLTTY.
  That support has now been discontinued.  If you have one and want to
  use it with Linux then that may be possible by using this version of
  the software.


  Blazie Engineering
  105 East Jarrettsville Rd.
  Forest Hill, MD 21050
  U.S.A.




     Phone
        +1 (410) 893-9333

     FAX
        +1 (410) 836-5040

     BBS
        +1 (410) 893-8944

     E-Mail
        <info@blazie.com>

     WWW
        <http://www.blazie.com/>



  7.5.2.1.  Blazie AT Products


  o  Braille Lite (support discontinued)



  7.5.3.  Digital Equipment Corporation


  Digital Equipment Corporation
  P.O. Box CS2008
  Nashua
  NH 03061-2008
  U.S.A




     Order
        +1 800-722-9332

     Tech info
        +1 800-722-9332

     FAX
        +1 603-884-5597

     WWW
        <http://www.digital.com/>


  7.5.3.1.  Linux Supported DEC AT Products


  o  DECTalk Express


  7.5.4.  Kommunikations-Technik Stolper GmbH


  KTS Stolper GmbH
  Herzenhaldenweg 10
  73095 Albershausen
  Germany




     Phone
        +49 7161 37023

     Fax
        +49 7161 32632


  7.5.4.1.  Linux Supported KTG AT Products


  o  Brailloterm


  8.  Software Packages

  References in this section are taken directly from the Linux Software
  map which can be found in all standard places for Linux documentation
  and which lists almost all of the software available for Linux.


  8.1.  Emacspeak

  Emacspeak is the software side of a speech interface to Linux.  Any
  other character based program, such as a WWW browser, or telnet or
  another editor can potentially be used within emacspeak.  The main
  difference between it and normal screen reader software for such
  operating systems as DOS is that it also has a load more extra
  features.  It is based in the emacs text editor.

  A text editor is generally just a program which allows you to change
  the contents of a file, for example, adding new information to a
  letter.  Emacs is in fact far beyond a normal text editor, and so this
  package is much more useful than you might imagine.  You can run any
  other program from within emacs, getting any output it generates to
  appear in the emacs terminal emulator.

  The reason that emacs is a better environment for Emacspeak is that it
  can can understand the layout of the screen and can intelligently
  interpret the meaning of, for example, a calendar, which would just be
  a messy array of numbers otherwise.  The originator of the package
  manages to look after his own Linux machine entirely, doing all of the
  administration from within emacs.  He also uses it to control a wide
  variety of other machines and software directly from that machine.

  Emacspeak is included within the Debian Linux distribution and is
  included as contributed software within the Slakware distribution.
  This means that it is available on many of the CDROM distributions of
  Linux.  By the time this is published, the version included should be
  5 or better, but at present I only have version 4 available for
  examination.



















  Begin3
  Title:          emacspeak - a speech output interface to Emacs
  Version:        4.0
  Entered-date:   30MAY96
  Description:    Emacspeak is the first full-fledged speech output
                  system that will allow someone who cannot see to work
                  directly on a UNIX system. (Until now, the only option
                  available to visually impaired users has been to use a
                  talking PC as a terminal.) Emacspeak is built on top
                  of Emacs. Once you start emacs with emacspeak loaded,
                  you get spoken feedback for everything you do. Your
                  mileage will vary depending on how well you can use
                  Emacs.  There is nothing that you cannot do inside
                  Emacs:-)
  Keywords:       handicap access visually impaired blind speech emacs
  Author:         raman@adobe.com (T. V. Raman)
  Maintained-by:  jrv@vanzandt.mv.com (Jim Van Zandt)
  Primary-site:   sunsite.unc.edu apps/sound/speech
                  124kB   emacspeak-4.0.tgz
  Alternate-site:
  Original-site:  http://www.cs.cornell.edu /pub/raman/emacspeak
                  123kB   emacspeak.tar.gz/Info/People/raman/emacspeak/emacspeak.tar.gz
  Platforms:      DECtalk Express or DEC Multivoice speech synthesizer,
                  GNU FSF Emacs 19 (version 19.23 or later) and TCLX
                  7.3B (Extended TCL).
  Copying-policy: GPL
  End





  8.2.  BRLTTY

  This is a program for running a serial port Braille terminal.  It has
  been widely tested and used, and supports a number of different kinds
  of hardware (see the Linux Software Map entry below).

  The maintainer is, Nikhil Nair <nn201@cus.cam.ac.uk>.  The other
  people working on it are Nicolas Pitre <nico@cam.org> and Stephane
  Doyon <doyons@jsp.umontreal.ca>.  Send any comments to all of them.

  The authors seem keen to get support in for more different devices, so
  if you have one you should consider contacting them.  They will almost
  certainly need programming information for the device, so if you can
  contact your manufacturer and get that they are much more likely to be
  able to help you.

  A brief feature list (from their README file) to get you interested


  o  Full implementation of the standard screen review facilities.

  o  A wide range of additional optional features, including blinking
     cursor and capital letters, screen freezing for leisurely review,
     attribute display to locate highlighted text, hypertext links, etc.

  o  `Intelligent' cursor routing.  This allows easy movement of the
     cursor in text editors etc. without moving the hands from the
     Braille display.

  o  A cut & paste function.  This is particularly useful for copying
     long filenames, complicated commands etc.

  o  An on-line help facility.

  o  Support for multiple Braille codes.

  o  Modular design allows relatively easy addition of drivers for other
     Braille displays, or even (hopefully) porting to other Unix-like
     platforms.



       Begin3
       Title:          BRLTTY - Access software for Unix for a blind person
                                using a soft Braille terminal
       Version:        1.0.2, 17SEP96
       Entered-date:   17SEP96
       Description:    BRLTTY is a daemon which provides access to a Unix console
                       for a blind person using a soft Braille display (see the
                       README file for a full explanation).

                       BRLTTY only works with text-mode applications.

                       We hope that this system will be expanded to support
                       other soft Braille displays, and possibly even other
                       Unix-like platforms.
       Keywords:       Braille console access visually impaired blind
       Author:         nn201@cus.cam.ac.uk (Nikhil Nair)
                       nico@cam.org (Nicolas Pitre)
                       doyons@jsp.umontreal.ca (Stephane Doyon)
                       jrbowden@bcs.org.uk (James Bowden)
       Maintained-by:  nn201@cus.cam.ac.uk (Nikhil Nair)
       Primary-site:   sunsite.unc.edu /pub/Linux/system/Access
                       110kb brltty-1.0.2.tar.gz (includes the README file)
                         6kb brltty-1.0.2.README
                         1kb brltty-1.0.2.lsm
       Platforms:      Linux (kernel 1.1.92 or later) running on a PC or DEC Alpha.
                       Not X/graphics.
                       Supported Braille displays (serial communication only):
                         - Tieman B.V.: CombiBraille 25/45/85;
                         - Alva B.V.: ABT3xx series;
                         - Telesensory Systems Inc.: PowerBraille 40 (not 65/80),
                           Navigator 20/40/80 (latest firmware version only?).
       Copying-policy: GPL
       End





  8.3.  Screen

  Screen is a standard piece of software to allow many different
  programs to run at the same time on one terminal.  It has been
  enhanced to support some Braille terminals (those from Telesensory)
  directly.


  8.4.  Rsynth

  This is a speech synthesiser listed in the Linux Software Map.  It
  doesn't apparently work well enough for use by a visually impaired
  person.  Use hardware instead, or improve it.. a free speech
  synthesiser would be really really useful.


  8.5.  xocr

  xocr is a package which implements optical character recognition for
  Linux.  As with Rsynth, I don't think that this will be acceptable as
  a package for use as a sole means of input by a visually impaired
  person.  I suspect that the algorithm used means that it will need to
  be watched over by someone who can check that it is reading correctly.
  I would love to be proved wrong.


  8.6.  xzoom

  xzoom is a screen magnifier, in the same vein as xmag, but
  sufficiently better to be very useful to a visually impaired person.
  The main disadvantages of xzoom are that it can't magnify under
  itself, that some of the key controls aren't compatible with fvwm, the
  normal Linux window manager and that it's default configuration
  doesn't run over a network (this can be fixed at some expense to
  speed).  Apart from that though, it's excellent.  It does continuous
  magnification which allows you to, for example, scroll a document up
  and down, whilst keeping the section you are reading magnified.
  Alternatively, you can move a little box around the screen, magnifying
  the contents and letting you search for the area you want to see.
  xzoom is also available as an rpm from the normal RedHat sites, making
  it very easy to install for people using the rpm system (such as
  Redhat users).



       Begin3
       Title:          xzoom
       Version:        0.1
       Entered-date:   Mar 30 1996
       Description:    xzoom can magnify (by integer value) rotate
                       (by a multiple if 90 degrees) and mirror about
                       the X or Y axes areas on X11 screen
                       and display them in it's window.
       Keywords:       X11 zoom magnify xmag
       Author:         Itai Nahshon <nahshon@best.com>
       Maintained-by:  Itai Nahshon <nahshon@best.com>
       Primary-site:   sunsite.unc.edu
                       probably in /pub/Linux/X11/xutils/xzoom-0.1.tgz
       Platforms:      Linux+11. Support only for 8-bit depth.
                       Tested only in Linux 1.3.* with the XSVGA 3.1.2
       driver.
                                       Needs the XSHM extension.
       Copying-policy: Free
       End





  8.7.  NFBtrans

  nfbtrans is a multi-grade Braille translation program distributed by
  the National Federation for the Blind in the U.S.A.  It is released
  for free in the hope that someone will improve it.  Languages covered
  are USA English, UK English, Spanish, Russian, Esperanto, German,
  Biblical Hebrew and Biblical Greek, though others could be added just
  by writing a translation table.  Also covered are some computer and
  math forms.  I have managed to get it to compile under Linux, though,
  not having a Braille embosser available at the present moment I have
  not been able to test it.

  NFBtrans is available from <ftp://nfb.org/ftp/nfb/braille/nfbtrans/>.
  After downloading it, you will have to compile it.



  8.7.1.  Compiling NFBtrans on Linux

  I have returned this patch to the maintainer of NFBtrans and he says
  that he has included it, so if you get a version later than 740, you
  probably won't have to do anything special.  Just follow the
  instructions included in the package.



          unzip -L NFBTR740.ZIP   #or whatever filename you have
          mv makefile Makefile





  Next save the following to a file (e.g. patch-file)



       *** nfbpatch.c.orig     Tue Mar 12 11:37:28 1996
       --- nfbpatch.c  Tue Mar 12 11:37:06 1996
       ***************
       *** 185,190 ****
       --- 185,193 ----
           return (finfo.st_size);
         }                /* filelength */

       + #ifndef linux
       + /* pretty safe to assume all linux has usleep I think ?? this should be
       + done properly anyway */
         #ifdef SYSVR4
         void usleep(usec)
           int usec;
       ***************
       *** 195,200 ****
       --- 198,204 ----
       UKP  }                /* usleep */

         #endif
       + #endif

         void beep(count)
           int count;




  and run



       patch < patch-file




  then type



       make




  and the program should compile.


  8.8.  UnWindows

  UnWindows is a package of access utilities for X which provides many
  useful facilities for the visually impaired (not blind).  It includes
  a screen magnifier and other customised utilities to help locate the
  pointer.  UnWindows can be downloaded from
  <ftp://ftp.cs.rpi.edu/pub/unwindows>.

  As it comes by default, the package will not work on Linux because it
  relies on special features of Suns.  However, some of the utilities do
  work and I have managed to port most of the rest so this package may
  be interesting to some people.  My port will either be incorporated
  back into the original or will be available in the BLINUX archives
  (see ``WWW references'').  The remaining utility which doesn't yet
  work is the configuration utility.

  In my version the programs, instead of generating sounds themselves,
  just call another program.  The other program could for example be



       play /usr/lib/games/xboing/sounds/ouch.au




  Which would make the xboing ouch noise, for example it could do this
  as the pointer hit the left edge of the screen.


  8.8.1.  dynamag

  dynamag is a screen magnification program.  please see the section on
  Screen magnification (``magnification'').  This program worked in the
  default distribution.


  8.8.2.  coloreyes

  coloreyes makes it easy to find the pointer (mouse) location.  It
  consists of a pair of eyes which always look in the direction of the
  pointer (like xeyes) and change color depending on how far away the
  mouse is (unlike xeyes).  This doesn't work in the default
  distribution, but the test version, at the same location, seems to
  work.


  8.8.3.  border

  border is a program which detects when the pointer (mouse) has moved
  to the edge of the screen and makes a sound according to which edge of
  the screen has been approached.  The version which is available uses a
  SUN specific sound system.  I have now changed this so that instead of
  that, it just runs a command, which could be any Linux sound program.


  8.8.4.  un-twm

  The window manager is a special program which controls the location of
  all of the other windows (programs) displayed on the X screen.  un-twm
  is a special version which will make a sound as the pointer enters
  different windows.  The sound will depend on what window has been
  entered.  The distributed version doesn't work on linux because, like
  border it relies on SUN audio facilities.  Again I already have a
  special version which will be avaliable by the time you read this.


  9.  Hardware

  9.1.  Braille terminals driven from Screen Memory

  These are Braille terminals that can read the screen memory directly
  in a normal text mode.  It is possible to use it to work with Linux
  for almost all of the things that a seeing user can do on the console,
  including installation.  However, it has a problem with the scrolling
  of the normal Linux kernel, so a kernel patch needs to be applied.
  See ``Patching the Kernel for Braillex and Brailloterm''.


  9.1.1.  Braillex

  The Braillex is a terminal which is designed to read directly from the
  Screen memory, thus getting round any problems with MS-DOS programs
  which don't behave strangely.  If you could see it on screen, then
  this terminal should be able to display it in Braille.  In Linux,
  unfortunately, screen handling is done differently from MS-DOS, so
  this has to be changed somewhat.

  To get this terminal to work, you have to apply the patch given below
  in section ``Patching the Kernel''.  Once this is done, the Braillex
  becomes one of the most convenient ways to use Linux as it allows all
  of the information normally available to a seeing person to be read.
  Other terminals don't start working until the operating system has
  completely booted.

  The Braillex is available with two arrangements of Braille cells (80x1
  or 40x2) and there is a model, called the IB 2-D which also has a
  vertical bar to show information about all of the lines of the screen
  (using 4 programmable dots per screen line)


  Price: 8,995  (pounds sterling) or 11495 UKP for 2-D
  Manufacturer: Alphavision Limited (UK)
  Suppliers: ????




  9.1.2.  Brailloterm

  ``What is Brailloterm?


  It's a refreshable display Braille, made by KTS Kommunikations-Technik
  Stolper GmbH.  It has 80 Braille cells in an unique line. Each cell
  has 8 dots that are combined (up/down) to represent a character. By
  default, Brailloterm shows me the line in which the screen cursor is.
  I can use some functions in Brailloterm to see any line in the
  screen.'' - Jose Vilmar Estacio de Souza <jvilmar@embratel.net.br>


  Jose then goes on to say that the terminal can also use the serial
  port under DOS but that it needs a special program.  I don't know if
  any of the ones for Linux would work.


  As with Braillex, this needs a special patch to the kernel work
  properly.  See section ``Patching the Kernel''.

  Price: about 23.000,- DM /  $ 15.000,
  Manufacturer: Kommunikations-Technik Stolper GmbH
  Suppliers: ????





  9.1.3.  Patching the Kernel for Braillex and Brailloterm

  This probably also applies to any other terminals which read directly
  from screen memory to work under MS-DOS.  Mail me to confirm any
  terminals that you find work.  This does not apply and will actually
  lose some features for terminals driven using the BRLTTY software.


  I am told this patch applies to all Kernels version 1.2.X.  It should
  also work on all Kernel versions from 1.1.X to 1.3.72, with just a
  warning from patch (I've tested that the patch applies to 1.3.68 at
  least).  From 1.3.75 the patch is no longer needed because the Kernel
  can be configured not to scroll using `linux no-scroll' at the LILO
  prompt.  See the Boot Prompt HOWTO for more details.




       *** drivers/char/console.c~     Fri Mar 17 07:31:40 1995
       --- drivers/char/console.c      Tue Mar  5 04:34:47 1996
       ***************
       *** 601,605 ****
         static void scrup(int currcons, unsigned int t, unsigned int b)
         {
       !       int hardscroll = 1;

               if (b > video_num_lines || t >= b)
       --- 601,605 ----
         static void scrup(int currcons, unsigned int t, unsigned int b)
         {
       !       int hardscroll = 0;

               if (b > video_num_lines || t >= b)




  To apply it:


  1. Save the above text to a file (say patch-file)

  2. change to the drivers/char directory of your kernel sources

  3. run


                       patch < patch-file





  4. Compile your kernel as normal


  Apply those patches and you should be able to use the Braille terminal
  as normal to read the Linux Console.
  Put in words, the patch just means `change the 1 to a 0 in the first
  line of the function scrup which should be near line 603 in the file
  drivers/char/console.c'.  The main thing about patch is that program
  understands this, and that it knows how to guess what to do when the
  Linux developers change things in that file.


  If you want to use a more modern kernel with completely disabled
  scrolling, (instead of the boot prompt solution I already mentioned),
  please use the following patch.  This does not apply to kernels
  earlier than 1.3.75.





       *** console.c~  Fri Mar 15 04:01:45 1996
       --- console.c   Thu Apr  4 13:29:48 1996
       ***************
       *** 516,520 ****
         unsigned char has_wrapped;          /* all of videomem is data of fg_console */
         static unsigned char hardscroll_enabled;
       ! static unsigned char hardscroll_disabled_by_init = 0;

         void no_scroll(char *str, int *ints)
       --- 516,520 ----
         unsigned char has_wrapped;          /* all of videomem is data of fg_console */
         static unsigned char hardscroll_enabled;
       ! static unsigned char hardscroll_disabled_by_init = 1;

         void no_scroll(char *str, int *ints)






  9.2.  Software Driven Braille Terminals

  The principle of operation of these terminal is very close to that of
  a CRT terminal such as the vt100.  They connect to the serial port and
  the computer has to run a program which sends them output.  At present
  there are two known programs for Linux.  BRLTTY, see section
  ``BRLTTY'') and Braille enhanced screen.


  9.2.1.  Tieman B.V.

  9.2.1.1.  CombiBraille

  This Braille terminal is supported by the BRLTTY software.  It comes
  in three versions with 25, 45 or 85 Braille cells.  The extra five
  cells over a standard display are used for status information.


  Price: around 4600 UKP for the 45 cell model ...
  Manufacturer: Tieman B.V.
  Suppliers: Concept Systems, Nottingham, England (voice +44 115 925 5988)




  9.2.2.  Alva B.V.

  The ABT3xx series is supported in BRLTTY.  Only the ABT340 has been
  confirmed to work at this time.  Please pass back information to the
  BRLTTY authors on other models.


  Price: 20 cell - 2200 UKP; 40 cell 4500 UKP; 80 cell 8000 UKP
  Manufacturer: Alva
  Suppliers: Professional Vision Services LTD, Hertshire, England
             (+44 1462 677331)




  9.2.3.  Telesensory Systems Inc. displays

  Because they have provided programming information to the developers,
  the Telesensory displays are supported both by BRLTTY and screen.


  9.2.3.1.  Powerbraille

  There are three models the 40, the 65 and the 80.  Only the 40 is
  known to be supported by BRLTTY.


  Price: 20 cell - 2200 UKP; 40 cell 4500 UKP; 80 cell 8000 UKP
  Manufacturer: Alva
  Suppliers: Professional Vision Services LTD, Hertshire, England
             (+44 1462 677331)




  9.2.3.2.  Navigator

  Again there are three models the 20, the 60 and the 80.  Recent
  versions are all known to work with BRLTTY but whether earlier ones
  (with earlier firmware) also work has not been confirmed.


  Price: 80 cell 7800 UKP
  Manufacturer: Alva
  Suppliers: Professional Vision Services LTD, Hertshire, England
             (+44 1462 677331)




  9.2.4.  Braille Lite

  This is more a portable computer than a terminal.  It could, however,
  be used with BRLTTY version 0.22 (but not newer versions) as if it was
  a normal Braille terminal.  Unfortunately, many of the features
  available with the CombiBraille cannot be used with the Braille Lite.
  This means that it should be avoided for Linux use where possible.


  Price: $3,395.00
  Manufacturer: Blazie Engineering




  9.3.  Speech Synthesisers

  Speech synthesisers normally connect to the serial port of a PC.
  Useful features include

  o  Braille labels on parts

  o  Many voices to allow different parts of document to be spoken
     differently

  o  Use with headphones (not available on all models)

  The critical problem is that the quality of the speech.  This is much
  more important to someone who is using the speech synthesiser as their
  main source of information than to someone who is just getting neat
  sounds out of a game.  For this reason T.V. Raman seems to only
  recommend the DECTalk.  Acceptable alternatives would be good.


  9.3.1.  DECTalk Express

  This is a hardware speech synthesiser.  It is recommended for use with
  Emacspeak and in fact the DECTalk range are the only speech
  synthesisers which work with that package at present.  This
  synthesiser has every useful feature that I know about.  The only
  disadvantage that I know of at present is price.


  Price: $1195.00
  Manufacturer: Digital Equipment Corporation

  Suppliers: Many.  I'd like details of those with Specific Linux
          support / delivering international or otherwise of note only
          please.  Otherwise refer to local organisations.
          Digital themselves or the Emacspeak WWW pages.





  9.3.2.  Accent SA

  This is a synthesiser made by Aicom Corporation.  An effort has begun
  to write a driver for it however help is needed.  Please see
  <http://www.cyberspc.mb.ca/~astrope/speak.html> if you think you can
  help.



  9.3.3.  SPO256-AL2 Speak and Spell chip.

  Some interest has been expressed in using this chip in self built
  talking circuits.  I'd be interested to know if anyone has found this
  useful.  A software package speak-0.2pl1.tar.gz was produced by David
  Sugar <dyfet@tycho.com>.  My suspicion, though, is that the quality of
  the output wouldn't be good enough for regular use.


  10.  Acknowledgements

  Much of this document was created from various information sources on
  the Internet, many found from Yahoo and DEC's Alta Vista Search
  engine.  Included in this was the documentation of most of the
  software packages mentioned in the text.  Some information was also
  gleaned from the Royal National Institute for the Blind's helpsheets.

  T.V. Raman, the author of Emacspeak has reliably contributed comments,
  information and text as well as putting me in touch with other people
  who he knew on the Internet.


  Kenneth Albanowski <kjahds@kjahds.com> provided the patch needed for
  the Brailloterm and information about it.

  Roland Dyroff of S.u.S.E. GmbH (Linux distributors and makers of
  S.u.S.E. Linux (English/German)) looked up KTS Stolper GmbH at my
  request and got some hardware details and information on the
  Brailloterm.

  The most major and careful checks over of this document were done by
  James Bowden, <jrbowden@bcs.org.uk> and Nikhil Nair
  <nn201@cus.cam.ac.uk>, the BRLTTY authors who suggested a large number
  of corrections as well as extra information for some topics.

  The contributors to the blinux and linux-access mailing lists have
  contributed to this document by providng information for me to read.

  Mark E. Novak of the Trace R&D centre <http://trace.wisc.edu/> pointed
  me in the direction of several packages of software and information
  which I had not seen before.  He also made some comments on the
  structure of the document which I have partially taken into account
  and should probably do more about.

  Other contributors include Nicolas Pitrie and Stephane Doyon.

  A number of other people have contributed comments and information.
  Specific contributions are acknowledged within the document.

  This version was specifically produced for RedHat's Dr. Linux book.
  This is because they provided warning of it's impending release to
  myself and other LDP authors.  Their doing this is strongly
  appreciated since wrong or old information sits around much longer in
  a book than on the Internet.

  No doubt you made a contribution and I haven't mentioned it.  Don't
  worry, it was an accident.  I'm sorry.  Just tell me and I will add
  you to the next version.






























