of816 VS LiaraForth

I also found this Forth implementation that might work.

There are several Forth versions for the 65816 that I've found online. Some are specialized to specific hardware but can be modified. Michael Guidero's OF816 is designed to be easily ported to new systems. I got it running on my 65816 emulator without much problem. It handles banked memory and uses a good subset of 65816 features.

One issue I had when I was finishing up my emulator was finding substantial programs to test that weren't designed for a particular architecture. I'm focused mainly on text-based programs, so it might not be as interesting for your emulation, but OF816, by Michael Guidero, is a larger program designed to be easily ported to new 65816-based systems. Here's my fork of it for my py65816 emulator as another example of porting it to an emulator. If you don't want to bother creating your own port or creating a binary, here's one with I/O mapped to 7FC0 and 7FE0 respectively. Load it at $8000 and reset to start. It uses bank 0 and bank 1 so you need to have at least those modeled.

Scot W. Stevenson's Liara Forth is designed to run on a W65C265SXB development board but could be modified to work on other hardware. I modified the binary file to run on my emulator for testing purposes. I believe it runs only in bank 0 and it doesn't particularly take advantage of many 65816 features.

I got my w65c265sxb board up and running with the help of the A Most Very Unofficial Guide to the W65C265SXB and Liara Forth. I found it very helpful to have a fully functioning program to start learning the 65816's new modes.

It was a bigger project than I thought, but I was able to get a version of Liara Forth, by Scot W. Stevenson, running last night (Liara Forth was designed for the W65C265SXB development board which has a 65C816 at its core).