An Asynchronous Microprocessor
Doug Edwards
For: Anybody brave enough
Abstract:
Two circuit design design styles can be identified: synchronous in which a
clock is used to separate consecutive system states from one another and
asynchonous in which there is no common clock and in which states are
defined in terms of input values and internal actions. Most hardware
systems are synchronous because timing issues are restricted to the moment
in time when the clock changes leading to ease of design. However there has
recently, for a number of reasons, been in resurgence of interest in
asynchronous techniques. The AMULET group within the
department has developed an asynchronous version of the well-known ARM microprocessor. A second, improved,
version (AMULET2e) is now complete.
This project is tackle the design of a simple asynchronous RISC
microprocessor, STUMP, which in its synchronous form is used as a
laboratory project for 2nd year students. The processor is a 16 bit
machine with a very restricted instrcution set and lacks the
complications such as an exception mechanism that normally makes life
difficult for hardware designers. If successful, it is envisaged that
the design could be used as a case study for undergraduate courses.