This directory contains a simple implementation of the B4 environment that works with the free pascal compiler.
- stack based virtual machine (ub4.pas)
- assembler (ub4a.pas)
- visual debugger (b4.pas)
- test suite (testb4a.pas)
- a small imperative testing framework (tptester.pas)
This code was originally written in turbo pascal 5.5 for MS-DOS (which you can download for free and run either on an old dos/windows box or inside dosbox).
I don't know if this code still works with turbo pascal, but free pascal is a much more capable compiler, and also runs on MS-DOS, as well as about a zillion other operating systems and architectures... So if you're looking for retrocomputing support, fpc is probably the way to go.