An object-oriented nano-kernel for operating system hardware support

The nano-kernel in the μChoices operating system provides hardware support for the operating system. The nano-kernel is a single, modular subsystem that encapsulates the hardware and presents an idealized machine architecture to the rest of the system. Higher levels of the system that implement policy access the nano-kernel through a single interface. Thus the μChoices nano-kernel is fully decoupled from higher level abstractions such as virtual memory or process paradigms. Within the nano-kernel, the hardware is modeled as a collection of abstract classes in a hardware support framework that are subclassed for particular hardware platforms. This architecture provides a highly modular and portable design making the system vastly easier to work with than previous versions of Choices. We have implemented a prototype of μChoices that runs on UNIX