TaliForth2 VS abn6502

Note that I've coded the debug window to work with my hardware binary which supports interrupts. As such it's somewhat specialized to my build and likely wouldn't work with your build without modification. Let me know if you're interested and I could point out changes needed for you build. Alternatively, I could fork the py65 GitHub and prepare a working version with my build's binary. As an added benefit you could play with my Forth operating system (though if your main interest is that then I'd recommend some better tested versions for the 6502, like Tali Forth 2 for example).

For a command line program I started out with getting WOZMON working and then began adding more capabilities similar to the Apple II system of old. I got tired of adding one-off functionality and discovered Forth when looking at programming languages suited for systems with limited resources. Look into TaliForth2 to get up and running fast on your 6502. The full program requires 24k ROM but can be slimmed down to fit in 16k pretty easily. I was inspired so I wrote my own Forth 2012 Standard version over the summer.

Get Taliforth running on it

I got tired of creating one-off functionality so I'm now working with Forth which is kind of like an operating system/programming language combined. It's pretty easing to get a version of that running on your 6502. Tali Forth 2 by Scott Stevenson ports pretty easily and has an editor, assembler and disassembler.

My code is a bit hard to read because of some APRS NRZ decoding mixed in with the KCS decoding but essentially I’m only measuring if the correct amount of cycles have passed(throwing away the other cycle data) and then detecting if the wave had a length above or below a threshold of $0600(somewhere around 1700Hz) timer1 counts (at 2MHz in my case). That leaves plenty of headroom but has pretty bad immunity to false zero crossings. You can have a look ca1irq: https://github.com/AndersBNielsen/abn6502/blob/main/abn6502rom.s

I’m using it for mine - same memory map as Ben’s. I only use the assembler for now though but will use the compiler some time in the future. It’ll probably help you get an idea how to set it up: https://github.com/AndersBNielsen/abn6502