I've been working for a while on my own implementation of Forth. I first used Forth in the '80s on my VIC-20, using a HES cartridge that was based on figFORTH. Coming back to 8-bit micros a year or two ago I wanted to build a more modern version that was better integrated with the Commodore KERNAL.

I started with the 6502 reference implementation which worked fine but the higher level words were defined in .WOR assembler statements. I experimented with using gForth to build a cross-compiler but it was rather messy keeping track of the different dictionaries, data sizes etc.

The next approach was to write a cross-compiler in Python. This proved far more straight-forward, I created abstractions for dictionaries, stacks etc that make debugging easy.

I've now got a fairly complete Forth-83 implementation that fits into 8K. It has words for file I/O, I've omitted the traditional block words. They made sense at the time but using editor words on a 22 x 23 display isn't very productive, in my opinion.

If anyone is interested the code and build tools are here

http://eden.mose.org.uk/vforth.git

I can attach snapshots if anyone doesn't want to build it themselves. I'd love to hear about other people's ideas or any feedback on my attempt.

Is there any source code? I wandered around http://eden.mose.org.uk/vforth.git and didn't find any, except I don't know how to open the files in the folders under "objects" although if they're object code then I don't expect to really get anything meaningful from them. I was particularly interested in the file operations, since I've never implemented them in my Forths for the workbench computer, as the host PC keeps the source code for them and that's where the editing is done, and every time any code is loaded, it comes from the PC as source code and the workbench computer compiles or assembles on the fly as it's receiving the source code from the PC via RS-232.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Sorry for not explaining, it's a git URL so you use



to get a local copy. I've attached a copy of my current work directory.

The file I/O words are defined in system.fs. They consist of a set of low-level words that interface with the standard Commodore KERNAL subroutines and a set of words that vaguely resemble ANS Forth.

Interesting. I cloned a copy and will take a look. I have a 6502 machine that has an IEC port and SD2IEC flash reader. It would be interesting to see if this is compatible.

I've run V-Forth on my FE3, it works well with SD2IEC.

The code uses normal KERNAL entrypoints where possible. There's some direct read/write of zero page, it should port to the C64 ok, not sure about others.

I've been making improvements to V-Forth, here's that latest version.