I started an experimental emulator project with PC I/O support, inspired by this thread:
6502 or W65C816S to X86 Assembly Language

I/O is done by strobing certain "magic" addresses. For example, this might output a character to the terminal:

(Note that the STA is trapped and ignored, and control is given to the I/O routine instead.)

The emulator is kinda working but there is no I/O yet besides a simple test. Keyboard, text, and file support should be possible, although I intend to keep it all pretty basic. Probably should be finishing existing projects instead of starting new ones, but oh well.

The code thus far:
https://github.com/Mortis69/6502PC

Nice.
I'm doing something similar, project in progress, 6502 emulation, possibly something more in the future.
Rudimentary character I/O is supported.
Blog entry:
http://leisureprogramming.blogspot.com/2016/02/virtual-machines-and-cpu-emulation.html
Code:
https://github.com/makarcz/vm6502
I already had Tiny Basic running in my emulator.

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Marek Karcz
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