The best implementation I know for Z80 is http://www.camelforth.com/
About - "MSX has a good technical specification for a Forth system"
I don't think so. Z80 is a proc which use 80% (depending your technical choices, it can be worst) of its time inside the forth VM.
Most of recent procs can reduce this time to 10%.
Maybe me, I own Kuma Forth complete set box-tape-manual and tape dump in cas.
So let me check this evening if I could help you (in the meanwhile, dump exists, see it in http://www.msxit.org )
I'm mainly interested in the contents of the instruction manual. To know the commands (words) defined to use the language/development environment. I've tried it out and it looks promising but it's no use without the documentation. It even has an interactive mode, so it seems like a full implementation of forth. I've also tried the Japanese one (HForce for msx-dos), there are good documentations (Japanese only) for that in the zip file and it looked like it is adapted very well for utilising MSX features, but it lacks interactive mode and has no editor, it is just a commandline compiler.
I'd like to compare these two in more depth.
a real one!
I had a quick read. It looks like the Japanese one (hForth) might be more practical option for development as it already defines MSX specific commands to do stuff. (although it lacks the interactive mode)
