| The CommunITel Viewdata System
was introduced as a package in 1985 by CommunITel Limited although
development of the package had begun in 1983. The market was mostly
educational and between 3000 - 5000 copies were sold. There were
two main versions of the package,
- a Level 1 - Local system designed to work on a stand
alone BBC microcomputer system with DFS or ADFS fitted or on a
networked BBC microcomputer fitted with an Econet interface.
- a Level 2 - Host system designed to work as both a
local system and as a host system providing access to viewdata
pages over the telephone lines using the CommunITel MODEM (other
MODEMs could also be used).
Both packages were substantial and came with detailed
documentation which would allow the more technical users to
customise the system for their own use.
Many viewdatabases were produced in schools using this system,
covering topics as diverse as Computer Science, Modern Foreign
Languages, English, Health Care and Administration. Sadly almost all
these databases have not survived.
The growth of the internet in the 1990s and the development of
ever faster data links sounded the death-knell for viewdata-like
systems and saw the demise of systems like PRESTEL and Teletext.
At the start of 2020 the Archive was fortunate to be gifted a
large collection of development material for the CommunITel Viewdata
System by its chief developer, Bill Olivier. Included in this
collection were;
- hundreds of floppy disks of different versions,
- floppy disks of the source code for the various component
programs used by the system,
- annotated listings,
- provisional documentation,
- copies of the software used to compress the BASIC program
listings for the released versions so that they would work on
BBC microcomputers with DFS and NFS fitted,
- technical documentation, including the file structure of the
DFS random access database yclept "VWDB".
Please use the links below to access the archive of CommunITel
material.
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DOCUMENTATION |
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This is the
Provisional Manual for the CommuITel System. The date is
uncertain but is probably some time in 1984. The
manual was the one amended by the developers preparatory
to producing the final manual. It contains many editing
notes. |
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This is the
Level 1 Reference Manual covering the stand alone and
local host system. |
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This is the
Level 1 Tutorial Guide covering the stand alone and
local host system. |
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Bill Olivier's
Business card as Technical Director |
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An internal
document outlining the structure and function of the
CommunITel Vewdata System |
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The CommunITel
Viewdata System uses a proprietary direct access filing
system to store pages on a floppy disk. BBC micro floppy
discs are limited to 31 entries. The direct access
filing system allows up to 195 pages on a single 80
track floppy disk, although the theoretical limit is
255. This document has been retyped by the Archive
from the original, faded computer printout.
Viewdata frames are stored in a single file, VWDB.
A machine code hashing algorithm is used to place the
files into the database for speed of access. |
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The notes for
the ADFS version of the Viewdata System. These are the
prototype notes produced before including in the Level 2
manual. The print quality of the original was poor.
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SOFTWARE |
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Source Files |
This is the set of CommunITel Viewdata System source
files dated September 1985. There are seven discs in the
set, numbered 0 to 6.
Disc 0, Disc 1,
Disc 2,
Disc 3,
Disc 4,
Disc 5,
Disc 6 |
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Prototype Random
Access Procedures |
The DFS version of the Viewdata System uses a single
large file, VWDB, to create a random access filing
system to get around the 31 file limit in the disc
catalogue. In this way up to 195 viewdata frames can be
stored in the single file. A hashing algorithm is used
to allow direct access to each frame using its frame ID
as the key.
Prototype source
files,
Annotated listing |
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Development Archive |
This is the complete collection of discs donated by Bill
Olivier. Each disc is numbered and an Excel spreadsheet
file is included to index the discs' contents. The
collection contains much development work and prototype
documentation in Wordwise Plus format.
The physical discs and the associated hard copy
material have been donated to the Centre for Computing
History in Cambridge.
The Archive |
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