The NSR processor

The NSR (Non-Synchronous RISC) processor is a general-purpose computer structured (IS U collection of self-timed blocks that operate concurrently and communicate over bundled data channels in the style of micropipelines [3, 16]. These blocks correspond to standard synchronous pipeline stages such us Instruction Fetch, Instruction Decode, Execute, Memory and register File, but each operates concurrently as a separate self-timed process. In addition to being internally self-timed, the units are decoupled through self-timed FIFO queues between each of the units which allows U high degree of overlap in instruction execution. Branches, jumps, and memory accesses are also decoupled through the use of additional FIFO queues which can hide the execution latency of these instructions. A prototype implementation of the NSR processor has been constructed using Actel FPGAs (Field Programmable Gate Arrays).