The problem with starting at a high level, e.g., BASIC or one of the other "hand-holding" interpreted languages is too much is automatic, making the mechanics of what is happening opaque. That's fine if your goal is to crank out a working program as quickly as possible without dealing with too many ...

Nice work! Implementing something like this is non-trivial. You have my respect. Liddicoat and Flynn would be proud.

I don't recognize all of the opcodes as 65C02, like "swp a" and "dup a". The 65816 had an XBA, which swapped the byte order of the accumulator. Where is the 65C02A documentation

FWIW there's AppleWin (Windows) and LinApple. We've recently done quite a bit of work on LinApple (there's plenty more to do). Since the Apple IIe had a built in monitor and disassembler, and the enhanced Apple IIe had a built in assembler, it's an excellent way to learn 6502 without a need for ...

Make _variable a volatile, to force the compiler to read it each time and prevent optimizing the infinite loop.