pyDOMESDAY
==========
pyDomesday is a 'pure python' emulator of the 1986 BBC Domesday system. It runs under Linux, and has been tested on
x64 and RaspberryPi 4.
Its aim is to provide a similar experience to the original, and also a platform for exploring the original software.
It is NOT a BBC micro (hardware) emulator! It instead tries to emulate the minimum of 'operating system'
functionality to enable the Domesday system to run.
Requirements.
-------------
1. Your own data! Re-creation of the Domesday project is plagued by the copyright issues of the original,
so you must have your own copies of .adl files for the National A, Community North and Community South disks, and
either still frames of all the video on the disks (only .jpg tested, so far) - or - if you are using the (optional)
OpenCV-python, .mp4 files of the three disks.
2. Pygame. This is (currently) used for the Domesday user interface.
3. Optionally:
If the py65 pure python assembler/disassembler package is installed, the software can emulate both at
the Cintcode level (the BCPL intermediate language that Domesday was implemented in) - as usual, or at the 6502
machine code level. Interpreting the Cintcode directly is much faster - but if py65 is available the system can
fall back to it if an unknown/unimplemented function crops up. Recommended.
If opencv-python is also available, pyDomesday will use it to display frames from an .mp4 file. This is much
more convenient than handling directories with 50,000+ jpg frames in them.
Running pyDomesday.
-------------------
cd to the directory where pyDomesday is downloaded. Edit BeebCfg.py to select display size and point to your data
files. Reduce the 'maxticks' value if you want the emulation to run more slowly.
Execute ./Beeb.py in a terminal. You will be presented with the Python Standard Library 'Cmd' interface. Type 'a',
'n' or 's' to select the domesday disk you want to view - the default is National A. Then press 'g' for 'go', and
you should be launched into a pygame window displaying the opening video sequence of your chosen disk.
Pressing the 'Pause' key during the emulation will return you to the 'Cmd' interface, where you can switch on
tracing, change execution modes, and so on.
Trace and print files are stored in the current directory.
Error handling is minimal - so expect crashes!
Acknowledgements
----------------
Dr. Martin Richards, the creator of BCPL, who provides and archive of BCPL and Domesday materianl on his web site.
Simon Inns and Ian Smallshire at Domesday86.com, for a wealth of Domesday material, their continuing efforts to
preserve laserdiscs, and in particular for rescuing the Archimedes version of the Domesday source code which
has been a great aid in understanding the software.
My uncle, who originally purchased a set of the Domesday disks, even though he never saw them running on a
Domesday system.
Steve M
October 2020