Introduction to the Domesday86 project


Domesday86 is a project that aims to recreate the experience of the original BBC Domesday project using modern hardware and software. On this site you will find a growing collection of documentation for the original Acorn/BBC Domesday project as well as details of the Domesday86 project itself including sub-projects such as BeebSCSI, SmallyMouse2 and the Domesday Duplicator.

Frame 00211 from Community South

The basic aim of the Domesday86 project is to create both hardware and software to allow the access and use of the Acorn BBC Domesday system (i.e. AIV - Advanced Interactive Video) without the need for specialist (and rare) parts of the original AIV set-up. Beginning with BeebSCSI (a hardware device that provides both ADFS SCSI and LV-DOS VFS SCSI support), Domesday86 aims to provide a complete suite of tools and utilities focused on the Acorn BBC and BBC Master range of 8-bit computers for viewing, analysing and using all of the AIV LaserVision discs, especially the 'Domesday' discs.

A complete BBC Domesday system running the National disc

In addition, this site aims to provide a comprehensive set of documentation for the original hardware covering design, operation and maintenance of the original AIV equipment such as the Philips VP415 LaserVision disc player.

The Domesday86 project

The overall concept of the Domesday86 project is shown in the following diagram:

Domesday86 Structure Diagram

The Domesday86 project comprises of several sub-projects that will work in unison to recreate the overall Acorn AIV/BBC Domesday system.  In addition, other elements, such as the 65C102 co-processor, are already freely available on the web.  The important difference between Domesday86 and other (previous) attempts to recreate Domesday is the fact that the concept is based on using the original BBC Master computer hardware.  Instead of attempting to emulate the entire system in software, Domesday86 uses a combination of the original hardware and new hardware.  This is important from the point-of-view of 'experience' - Domesday86 aims to allow users to access the AIV system as it was originally intended (i.e. from a BBC Master).  Another important difference is that the Domesday86 project is 100% open-hardware and GPL open-source software.  All parts of the completed design (software, firmware and hardware) are documented and free to download.

Domesday86 demonstration system running the BBC Domesday Community disc

So far the Domesday86 project has produced three major elements of the environment; namely SmallyMouse2, BeebSCSI and the Domesday Duplicator.  SmallyMouse2 emulates the Marconi RB2 trackerball device used by the original BBC Domesday system to control the on-screen GUI used by all of the AIV discs.  BeebSCSI emulates both the AIV SCSI host adapter and the SCSI elements of the Philips VP415 LaserVision player.  The VP415 can be logically split into two parts; firstly the SCSI LUN image provided by the VP415 (which is functionally equivalent to the original ADFS file system (and BeebSCSI can emulate both)) provides all of the data and software from the AIV discs.  Secondly, the VP415 also supported video/media control commands (called 'F-Codes') that allow the host computer to control the video, sound and still picture output of the VP415.

Rather than overcomplicate BeebSCSI, this emulation has been split apart.  BeebSCSI provides all of the SCSI interaction with the host computer and also provides a bi-directional serial connection to the 'media' part of the VP415.  This abstraction allows the project sub-parts to be more easily divided.  BeebSCSI takes care of the custom VP415 SCSI commands and allows the VP415 emulator to communicate using simple text-based F-Codes.  The VP415 emulator is then only responsible for providing the required video, sound and still-pictures as requested by the host.

The VP415 emulator is currently work in progress; the intention is to eventually provide the emulator as hardware along with a genlocking device that combines the VP415 video with the BBC Master's video (just as the original BBC Domesday system functioned).

The Domesday Duplicator project provides the technology required to digitize the analogue AIV laserdiscs and preserve not just pictures and sound, but also the digital information contained on the LV-ROMs.  The duplicator is a necessary stepping-stone on the road to emulating the original Philips VP415 laserdisc player as, without laserdisc information, the emulation would not function.

A BeebSCSI board fitted internally to a BBC Master Turbo

You can find much more information about the Domesday86 project in the other sections of this site.  Information is provided for the completed project items and for the items currently in progress.

The Domesday National Laserdisc