This is Motorola 6800 processor emulator, written entirely in Swift. Consider this as learning project for CPU itself and emulation.
You can implement and "map" input and output devices to processor address space. As an example - Heathkit ET-3400 keyboard and display. Non-modified, original Heathkit ROM works.
All credits for ETA-3400X project and ALTAIR 680 Basic port goes to Mark Cummings.