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-
- BRLTTY - Access software for Unix for a blind person
- using a soft Braille terminal
-
- Version 1.0, 26 July 1996
-
- Copyright (C) 1995, 1996 by Nikhil Nair and others. All rights reserved.
- BRLTTY comes with ABSOLUTELY NO WARRANTY.
-
- This is free software, placed under the terms of the
- GNU General Public License, as published by the Free Software
- Foundation. Please see the file COPYING, included in the BRLTTY
- distribution, for details.
-
- This software is maintained by Nikhil Nair <nn201@cus.cam.ac.uk>.
-
- -----------------------------------------------------------------------------
-
- INTRODUCTION FOR THOSE NEW TO SOFT BRAILLE
- ==========================================
-
- There are two common ways in which blind people access computers. The
- first, and more widely known, is synthesized speech, which, while having
- many advantages (e.g. speed for reading plain text), does have its
- drawbacks: speech output generally gives little information about
- formatting, making tables, spreadsheets etc. difficult to use; it can also
- be difficult to use speech output with particularly technical material
- containing lots of symbols (though many determined people do use it for
- such things).
-
- The other solution, which attempts to answer some of these problems, is
- Braille output. A soft (or refreshable) Braille display typically consists
- of a single row of either 20, 40 or 80 characters, each made up of a matrix
- of 4X2 (4 down, 2 across) dots. Each dot is individually driven by a
- separate motor, making the whole assembly extremely expensive.
-
- A soft Braille display would connect to a PC by either the serial or
- parallel port. Software on the PC drives the display, reproducing a
- rectangle of the screen image (which we will call the window) in Braille.
- Buttons on the Braille display itself are used to send signals back to the
- software, instructing it to move the window around the screen, or some
- other specialised function.
-
- With a soft Braille display of 40 or 80 cells, it is quite easy for a blind
- user to appreciate the format of information on the screen, and even allows
- the reading and editing of on-line Braille documents (a concept not widely
- enough utilised).
-
-
- INTRODUCTION TO BRLTTY
- ======================
-
- While soft Braille displays have been used for some years under MS-DOS, and
- are even starting to be used under Windows, it seems that they have not
- been used on Unix consoles. This could well be because blind people have
- been able to access Unix systems through accessible terminals. With the
- advent of PC-based Unix systems (such as Linux), the need becomes evident.
-
- BRLTTY attempts to fill this gap. It runs as a daemon, possibly started at
- boot-time, and allows a soft Braille user to access text mode applications.
- Since BRLTTY is written as a daemon, it should allow a user a completely
- free choice of application and development tools.
-
-
- FEATURES
- ========
-
- - Full implementation of the standard screen review facilities.
- - 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.
- - `Intelligent' cursor routing. This allows easy movement of the cursor
- in text editors etc. without moving the hands from the Braille
- display.
- - A cut & paste function. This is particularly useful for copying long
- filenames, complicated commands etc.
- - An on-line help facility.
- - Support for multiple Braille codes.
- - Modular design allows relatively easy addition of drivers for other
- Braille displays, or even (hopefully) porting to other Unix-like
- platforms.
-
-
- CURRENTLY SUPPORTED HARDWARE
- ============================
-
- BRLTTY requires Linux kernel 1.1.92 or later (for `/dev/vcsa0'). It has
- been tested on
- - a variety of PCs: both laptops and desktops; processors from
- 386SX20 to Pentium with a huge range of memory sizes; Linux
- distributions including Debian and Slackware; a number of Linux
- kernels, including both 1.2.13 and 2.0.0.
- - a DEC Alpha: only tested once, under RedHat Alpha Linux on a noname
- board kindly lent to the Cambridge University Computer Laboratory
- by DEC in Reading, England.
-
- The following Braille displays are supported (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?).
-
- If you want another Braille display to be supported, please contact
- the maintainer. Ability to add more Braille displays does, however,
- depend on the level of cooperation from the manufacturer in providing
- programming information.
-
-
- THE BRLTTY TEAM
- ===============
-
- There are currently three active developers:
- - Nikhil Nair: founder of the BRLTTY project and author of the
- Tieman B.V. CombiBraille driver
- E-Mail: nn201@cus.cam.ac.uk
- - Nicolas Pitre: Author of the driver for the Alva series
- E-Mail: nico@cam.org
- - Stephane Doyon: Author of the driver for the TSI displays (Navigator
- and PowerBraille 40)
- E-Mail: doyons@jsp.umontreal.ca
-
- Any comments and/or criticisms regarding BRLTTY in general should be
- addressed to all three of the above.
-
- In addition, James Bowden <jrbowden@bcs.org.uk>, the original coauthor, is
- now acting in an advisory capacity.
-
-
- LAYOUT OF THE ARCHIVE
- =====================
-
- BRLTTY is distributed as a single GNU compressed tarfile named
- brltty-<version>.tar.gz
- where `<version>' is the version number. When the archive is
- unpacked, there should be a subdirectory called DOCS: this contains
- all of the general BRLTTY documentation, including the manual in
- various formats and the list of frequently asked questions (FAQ).
-
- The source files for the main, device-independent core of BRLTTY is in
- the top-level directory. There is also one subdirectory per Braille
- device type, containing display-specific source files and
- documentation (in another README file).
-