Updated: JABT version 2.5
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jabt - Driver for the Alva Braille Terminal 3, 4 and 5 series.
[-a jabt_dir] [-c n] [-d device] [-h] [-p port] [-r]
[-s speed] [-t tab_file] [-V]
background program makes the Alva Braille Terminal to
follow the screen. It provides both a serial and a parallel driver.
To use the parallel driver, use the `-p' option.
If you want to use
in conjunction with
please give the following command before you start
setserial /dev/ttyS0 ^session_lockout
Without this command only one process is allowed to I/O with the serial port.
will read the information directly from the
screen (via the Virtual console capture device, see below) and
displays it on the ABT.
determines automatically which model is connected.
The status-cells of the ABT represent the following:
- cell 1
The line on the screen which hold the cursor
is represented by a letter; `a' is the top
line, `b' is line two and so on.
Alva Braille Terminal 320
Alva Delphi 420
If the display resides between column 20 and 40
dot 7 is set. If it resides between column 40
and 60 dot 8 is set. If the display resides
behind column 60 both dot 7 and dot 8 are set.
Alva Braille Terminal 340
Alva Braille Terminal 340 Desktop
Alva Delphi 440
Alva Delphi 440 Desktop
Alva Satellite 544
Alva Satellite 544 Traveller
If the display resides behind column 40 dot 8 is set.
- cell 2
The letter on this cell tells which line is
displayed on the ABT.
Dot 7 and 8 behave just like dot 7 and 8 of
- cell 3
This cell shows the number of the virtual console currently on screen.
If the current virtual console is in graphics mode, cells 1 and 2 are cleared
and the text `graphics screen' is displayed on the ABT.
A bold, reverse or blink attribute of a character will cause a setting
of dot 8 of that character.
Each virtual console has its own set of toggles. Each toggle (see
takes only effect on the current virtual console.
If a character is repeated more than 3 times,
will speak out that character followed by `n times', where n is the
number of the repetition.
uses the OGG/VorBis libraries to play samples when certain ABT_keys
are pressed. If there is no audio_device or the device cannot be opened,
will generate a beep. The samples are by default located
in the directory /opt/etc/jabt.
When the cursor reaches column 65,
will produce a beep. (Like the bell on an ancient typewriter.)
To avoid the ABT from wear and tear while a blinking
cursor is selected, the
will select a static cursor after three minutes of idle time.
(See the -c option.)
Screen-reading options are included using an external Text-To-Speech
will send messages to the system logger.
- -a jabt_directory
Sets the jabt_directory. If this option is
will default to
- -c n
Select cursor type.
1 = static block, 2 = blinking block
3 = static underline, 4 = blinking underline.
- -d device
This option tells
to which port the ABT
is connected. When no device is given,
writes to /dev/ttyS0.
This option displays the usage of
- -p port
Use this option to activate the parallel driver. Give a `1' argument to
select the first parallel port or a `2' argument for the second port.
Otherwise give the I/O-address of the parallel port as argument. (In most
cases `0x378' is the first parallel port and `0x3bc' is the second port.)
Use RTS/CTS hardware handshaking.
- -s speed
This option specifies the speed of the serial line.
The following speeds are available:
300, 1200, 2400, 4800, 9600, 19200 or 38400
baud. The default speed is 9600 baud.
- -t tab_file
If there is no braille-character-file in the
directory /opt/etc/jabt, such as
will defaults to the German braille-set.
Displays version of
The following keys and key-combinations are
Shows the last ASCII value selected by `prog+touch-key' on the status cells.
Puts the ABT in upper-left position. If `home' is pressed twice within
will jump to the lower-left position.
Sets the ABT on the line which contains the cursor. Suppresses the cursor
so that the under-laying character is visible. Meanwhile, the cursor
position is displayed on the status cells.
Puts the ABT one line up.
Puts the ABT 20 or 40 characters to the left, depending on the ABT model.
will give a short beep to indicate that the ABT is gone one line up.
Puts the ABT 20 or 40 characters to the right, depending on the ABT model.
will give a short beep to indicate that the ABT is gone one line down.
Puts the ABT down one line.
- status-touch-key 1
Toggles speech on or off. In `on' mode there are two modes. When in
first `on' mode the external TTS (see the `tts' file) will speak out
the typed character. When in second mode
will holds the typed characters. When a non-alphanumeric character is
pressed, the external TTS will speak out the whole word.
- status-touch-key 2
The external TTS will speak out the whole screen.
- status-touch-key 3
The external TTS will speak out the line currently displayed on the ABT.
If `status-touch-key 3' is pressed twice within 40 ms
will kill speech.
Select the first character of the text-block to be `cut out of the screen'.
If a touch-key is pressed again it selects the last character of the
text-block to be `cut out of the screen'.
The selected block will be viewed reverse on the screen.
Speak out the corresponding character or word if in character- or word-mode..
(see status-touch-key 1)
Toggles between displaying lowercase-only or
upper- and lowercase displaying.
Toggles between following the cursor or not.
Selects another cursor-type.
Puts the ABT 1 character to the left.
Puts the ABT 1 character to the right.
Toggles attribute-displaying. (Dot 8 on or off)
- prog+status-touch-key 1
Re-read the `tts' file. (if another TTS is desired.)
Each time this combination is pressed
will select the next TTS-command from this file. (if any, else the first one
will be selected. and so on)
- prog+status-touch-key 2
Toggle punctuation on or off.
When toggled on
will put each punctuation mark through to a punctuation.* file.
will replace each punctuation mark by a space, so that only alphabetic
characters and digits are spoken.
- prog+status-touch-key 3
Toggles speech on or off. When toggled on the external TTS (see the `tts'
file) will automatically read out the line currently displayed on the ABT
each time this line is changed.
Writes the ASCII value of the pointed
character on the status-cells.
Toggles type-writer bell on or off.
Toggles the demo mode on or off. When in demo mode
will put the text currently being displayed on the ABT in reverse,
so sighted people can see what the braille user is reading.
Insert the selected text-block at the cursor position.
encounters a punctuation mark, it will looked for in a punctuation.*
file. These punctuation.* files contains spelled words for each punctuation
mark. If no punctuation.* file is available, the punctuation mark
will be directly put through to the current tts-command. (Not all
speech synthesizers can correctly deal with punctuation marks.)
When the third status-touch-key is pressed twice within 40 ms,
will execute a command to silence the current TTS. The command to use
is specified by the third field on the TTS line in the `tts' file.
If the third field is not speciefied in the `tts' file,
will try to kill the synthesizer by its name specified in the first field
of the `tts' file.
reads its information from a device
/dev/vcsa, /dev/vcsa0, /dev/vcc/a or /dev/vcc/a0 (depending on the used
Linux distro). Kernels 1.1.92 or later provide this device.
Device to which the ABT is connected.
Conversion-tables for braille-characters.
Audio samples used by
This file contains the name(s) of the Text-To-Speech utility to be used.
Each line consists upto three fields separated by a semi-colon `;'.
Field 1: The TTS-command to be used.
Field 2: The name of the punctuation file to be used.
Field 3: The name of the command to silence the TTS.
Punctuation files. (See Field 2 above.)
stty(1L), vcs(4), xabt(1), setserial(8),
logger(1), syslog.conf(5), syslogd(8),
Jos Lemmens (email@example.com)
- Thanks to:
"The makers of BRLTTY:"
Eric Harbers from Alva for the parallel driver.
- PUNCTUATION FILE
- SILENCE COMMAND
- SEE ALSO