Architecture/Block diagram of basic Emulator

I want to understand working of basic Emulator.

Could you please provide me some basics (general architecture / block diagram) of general emulator.

OR any links for the same. If you can suggest some white paper published for the same then it will be helpful.

Thanks

PJ开发者_如何学Go

Virtual Machines: Versatile Platforms for Systems and Processes might work as a starting point.