AMULET is a series of microprocessors that implement the ARM processor architecture. Developed by the Advanced Processor Technologies group under the University of Manchester's computer science school (formerly the AMULET and PAL groups based at the same institution), AMULET is unique from other ARM implementations in that it is an asynchronous microprocessor, not making use of a square wave clock signal for data synchronization and movement.

List of AMULET Microprocessors

• AMULET1 - Designed in 1990 and first fabricated in 1993. Its estimated performance is approximately 70% of that of a comparably-sized synchronous ARM6 running at 20 MHz.
• AMULET2 - A re-implementation of AMULET1 first fabricated in 1996. Features on-chip memory that can be used either as processor cache or mapped RAM. The APT group estimates AMULET2 to have a similar power dissipation/performance ratio as ARM8. One very notable feature that is due to the asynchronous design is that the power dissipation drops to 3µW when not in use (assuming the on-board timer, which handles DRAM refresh, is also inactive).
• AMULET3 - This yet-incomplete processor aims to focus on performance more than the previous AMULET processors, whose main design concern was low power dissipation. It is expected to feature ARM level 4 instruction set compatibility, as well as support Thumb mode.

See Also

• ARM Architecture

External Links

• ARM Ltd.
• APT Group