This directory contains the BRLTTY driver for braille displays which are
manufactured by Handy Tech Elektronik GmbH [http://www.handytech.com/] of
Germany. As a component of BRLTTY, this driver is released under the terms of
the GNU Public License.

This driver was originally implemented by Andreas Gross <andi@andi-bika.de>. It
has since been extended, and is being maintained, by Dave Mielke
<dave@mielke.cc>. Thanks to Mike Pedersen <mpedersen@mindspring.com> for his
help with the design and testing of the Braille Star component. Thanks to Jill
Clark <jill@handytech.com> of Handy Tech Elektronik for having graciously lent
us a Bookworm so that its component could be tested. Thanks to Mario Lang 
<mlang@delysid.org> for his help with the development of USB and bluetooth 
support.

A HandyTech display can be used via its serial, USB, or bluetooth interface. If
you're using a serial connection then specify "serial:/path/to/device", e.g. 
"serial:/dev/ttyS0". If you're using a USB connection then specify "usb:" (the
trailing colon is important). If you're using a bluetooth connection then
specify "bluez:address", e.g. "bluez:01:23:45:67:89:AB".

Active Braille:
---------------

An external keyboard can be connected to your Active Braille via USB. The 
keyboard is presented to the host as though it were a true HID (Human Interface 
Device) in its own right. If you are using USB (not yet supported) to connect 
your Active Braille to the host, most modern operating systems will 
automatically recognize and correctly handle the keyboard. If you are using 
Bluetooth to connect your Active Braille to the host, you will need to do some 
additional setup to get the keyboard working.

For Bluetooth on Linux: Add the Bluetooth device address and the PIN of your 
Active Braille to the file /var/lib/bluetooth/<host-address>/pincodes so that 
it will successfully pair with the host. Then, to enable keyboard input from 
the Active Braille, execute the following command as root:

   bluez-test-input connect 00:01:02:03:04:05

Note that you will need to replace the sample Bluetooth device address in the 
example above with that of your Active Braille.

Basic Braille:
--------------

Starting with the Active Braille, Handy Tech has introduced a resistor 
which limits the amount of power drawn via USB. This eliminates 
excessive draining of the host's battery. This artificial reduction in 
power consumtion has the side effect that the dots do not lower as 
quickly. This leads to a kind of blurring when you scroll rapidly 
through a screen. If you are a user who does a lot of rapid scrolling, 
you will likely notice this effect. The Basic Braille allows this 
behaviour to be configured. If you can afford to draw a little more 
power via USB and would like to get rid of the blurring, here is how 
to configure it:

  Press all six display keys at once and hold for at least one second.
  You will see "Config mode" on the display.
  Now press cursor routing key 7 to toggle "HIGH USB POWER".
  Pressing display key 6 will leave Config mode.

The symmetry of the Basic Braille makes it easy to use when rotated 
180 degrees such that the routing keys are below (rather than above) 
the braille cells. If you would prefer to use your Basic Braille this 
way, simply press both the first and last routing keys simultaneously 
while in Config mode.

Braille Star:
-------------

Braille Star models allow the use of an external keyboard for input. It can be
used not only while the Braille Star is in "Notetaker" mode, i.e. while not
connected to any external PC hardware, but also as a keyboard for the PC
itself. Either connect the second PS/2 cable from your display to your PC
(that's the old way), or just disable "Ext. keyboard autoselect" in the
internal menu. This latter, much simpler, approach causes the keyboard's
signals to be sent over whatever interface (serial, USB, or bluetooth) you're
using to connect your display to your PC. It's particularly advantageous to use
the external keyboard in conjunction with a bluetooth connection since this
combination effectively transforms the Braille Star into a completely wireless
yet fully functional braille terminal.
