A processor for constructing a single processor system or multiprocessor system comprises, within a base processor element constituting the processor, two CPU with associated local memories, a dual-port RAM accessible from said CPUs, and a common bus switch circuit for connecting any one of said CPUs...http://www.google.de/patents/US5568617?utm_source=gb-gplus-sharePatent US5568617 - Processor element having a plurality of processors which communicate with each other and selectively use a common bus
