BEAM Ltd
XVI - A TECHNICAL OVERVIEW
BEAM Ltd - September 1995
Introduction
This document gives an overview of the use of a BEAM XVI terminal in a
typical networked system.
The Network System
A common approach when using Unix based systems is to use a limited
number of powerful servers together with Workstations all connected together
using a Unix Network. Users access the Servers either via a personal Workstations
or through an X-Terminal. The X-Terminal is a graphics user interface device
allowing a user to run Unix X-Window applications from any of the Servers
or Workstations.
With this system the applications run on either remote Unix Servers
or local Unix Workstations. The applications present their graphics onto
the display of the X-Windows Terminal via the network. This is different
to the Microsoft Windows approach where applications run on individual
personal computers on each desk. Both systems have merits and problems.
Some companies prefer one approach to the other and some use both approaches
on a common network.
The BEAM XVI Terminal
The BEAM XVI Terminal is like a conventional X-Windows Terminal with extensions
to help the visually impaired user see and manipulate applications. The
Beam XVI Terminal consists of a large colour monitor with keyboard and
mouse and a box containing the display control system. It has the appearance
of a conventional personal computer and is indeed based upon this technology.
The system box is available in one of three forms:
Slim-line under monitor box
Desktop box
Mini-Tower box
The Mini-Tower system is the most commonly used as it allows the
main box to be sited under the users desk leaving plenty of room on the
desk for working. It also has expansion slots available for adding future
XVI extensions such as a video camera document viewer.
The BEAM XVI Terminal is connected to the computing systems by means
of an Ethernet network cable. Both 10Base2 and 10BaseT networks are supported.
BEAM XVI Extensions
The XVI extensions include the following features:
Magnification of the whole screen to 8x normal size.
Manual and Automatic pan of the screen
Cursor colour modification
Background colour and style modification
Tracking of X-Windows Text cursors and Motif graphics
Magnifying glass which shows a zoomed portion around the cursor
User preferences modification
The BEAM user manual describes these features in more detail.
Implementation of BEAM Extensions
The BEAM XVI extensions have been implemented as an X-Windows extension
with a Motif client providing a user interface and other functions. This
method provides a high performance system with great flexibility for future
enhancements.
Installing a BEAM XVI Terminal
If the user is already using an X-Terminal changing to using a BEAM XVI
Terminal is simplicity itself. Just unplug the old X-terminal from the
network, plug in the BEAM XVI Terminal, setup the network address and all
is ready to use. There are no changes necessary to the host systems. All
of the XVI software extensions run on the BEAM XVI Terminal and thus have
no effect on the network system. The local software extensions are also
fast as the magnifier and other tools have direct access to the display
hardware.
If the user is using a Unix Workstation a BEAM X-Terminal can be situated
alongside. The Monitor of the Workstation can be removed. The Workstation
needs to be setup to present a user login, via xdm, on the BEAM XVI Terminal.
This is normally a simple operation. Indeed on some systems it is already
setup. The user can now login to the Workstation in a similar if not identical
manner to before, but now has the XVI extensions to assist them.
BEAM XVI Future Extensions
Future extensions planned include a video camera interface allowing users
to view documents zoomed in a window on the display terminal and a speech
output system. For information on these new features please contact BEAM.