This is a complete emulator of the original MOS Technology 6502 microcontroller from 1975. It is written in C++.
The emulator works by providing a shared memory bus, to which one can connect devices. Each device is allocated an address range, in which it can provide its functionality. This allows the program to change audio-output and draw graphics by simply writing a value to a specific address.
Below you can see the virtual monitor displaying a pong game. The game is implemented completely in the 6502-Assembly language.
Since the original 6502 didn't use all available opcodes, a custom one was added. You can see a list of unused 6502 opcodes here.
Instead of halting the CPU, it now waits until the next interrupt happens.
0x02 - WAISame behaviour as on the WDC 65C02.
- Leonard Schütz, Lead Developer @KCreate