EMMA2: a high-performance hierarchical multiprocessor

The development of a parallel system providing high computational power at a reasonable cost using inexpensive processors is described. The original motivation for the work, which led to the EMMA (Elaborate Multi-Mini Associativo) multicomputer, was the mechanization of mail sorting. The need for a system that could be the basis for a wider range of applications spurred the study and development of a new system, the EMMA2. The discussion covers EMMA2's characteristics, architecture, buses, standard modules, I/O, approach to coprocessors, and operating system.<
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