ICL 1900 Series Preservation

Many thanks to the work of David Holdsworth and Delwyn Holroyd, who obtained copies of the ICL issue tapes, backup tapes and documentation from the last live George 3 site, in the UK, while it was being decommissioned.

They have written a George 3 Executive Emulator which provides an environment in which George 3 Mk 8.67 can be run in either a Windows 32-bit or Linux environment. They have also obtained permission from Fujitsu (ICL) to preserve George 3 as an historical object for non-commercial use (which presumably must include the various other software needed to run a system).

In addition to the George 3 Executive Emulator, I am involved with a project to write 1900 hardware emulators.

Why other 1900 emulators, when there is already a perfectly good emulator which successfully runs George 3? There are several reasons:-

• G3EE will only run George 3
• Inaccurate emulation speed (runs much too fast)
• Limited peripheral types (but sufficient to run a reasonable system)

We have set out to achieve:-

• Hardware level emulation
• Reasonably accurate emulation of speed (processor and peripherals)
• Ability to run different Executives, Operating Systems and even diagnostics
• Emulation of a wide variety of peripheral types

We believe that there is a ‘market’ for both emulators, G3EE giving a quick and easy taste of a 1970s GEORGE 3 Operating System, supported by ICL 1967–1984 and known to be running as a production system until 2011 on a 2966 under CME; and the 1904S emulator giving a more realistic impression of those days. We used G3EE as a bootstrap for our project, which may not have got started without it – many thanks to David and Delwyn.

The documentation and software on this site has come from a variety of sources, and I am aways looking to add to this collection, both to preserve it for posterity and make copies available to other 1900 enthusiasts.