Only the most basic features have been implemented to date.
Eventual goal is to allow the emulator to load a .hex file containing a program, execute that program, and output to simulated accessories such as a display, or serial interface.
Realistically, this is abandoned. Enough instructions have been implemented to run a basic program, and unimplemented opcodes are designated 404. It's possible I will pick this up again, but probably not.
Want to contribute? You probably know more than me, so just shoot me a message.