This was my first large assembly program, written in the summer of 1983 (at the age of 16)

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This new version is the modern re-work of that original code. My ambition all those years ago was to turn my FORTH into a ROM image, sadly I never achieved this at the time.

The completed project is now available on github. (https://github.com/perfectconsulting/GSFORTH-ROM)

The performance gains over am indirect threaded model on a 6502 are substantial. GSFORTH is currently the only subroutine thread FORTH for the BBC Micro, and in most use cases is approximately twice as fast as Acorn FORTH or MultiFORTH.