This is an emulator for the Ferranti Pegasus Valve computer from the 1950's There are existing emulators, but they have a number of issues:-
1. DOS based and don't run on 64-bit Windows without use of DOSBOX
2. Use low-resolution bitmapped images so look odd on modern high-resolution screens.
3. "Closed Source" so they can't be modified.
This emulator is designed to overcome those issues.
This is giving me grief. The Pegasus Divide is a 77 bit number divided by a 38 bit number. When I first looked at the problem I wanted to do "proper" long division rather than repeated subtraction. However after reading the manuals I realized that that's actually what Pegasus does, so now I can start coding...