This was a fun thing to see after having just finished binging Ben Eaters 6502 breadboard computer series.

Since it's printing something out I suppose it also has everything else virtualised, would be cool to be able to provide it some machine code / assembly

I networked a 6502 a while ago in order to capture some behavior that isn't well documented.

You can interact with it using a wasm-based assembler in your browser. Programs only get 100 cycles to run but that should be plenty if you just want to poke around.

https://chiplab.emulationonline.com/6502/

How many layers of virtualisation do we need?

All of them :)

Run it in a browser in Wine on a MAC?

None of them run in a browser powered by WebAssembly. I created a 2D engine in C++20 based on SDL, in which I can use Lua to create games. Then I thought, “I’ll make a NES emulator,” so I started with its CPU, the 6502.

Have you run https://github.com/Klaus2m5/6502_65C02_functional_tests ?

See also https://www.righto.com/2012/12/the-6502-overflow-flag-explai...

I also note that you have the same code copy/pasted in every ALU operation which might be better expressed in one location for maintenance reasons.

Good call out. Thank you! I will give a try.

I’ve just updated the demo. Check it out here: https://carimbo.run/play/1.0.43/willtobyte/MOS6502/1.0.6/480...