Virtual shared memory interconnect bus provides real-time linkage between multiprocessors

Recent advances in computing and processor technology have brought mainframe computing power to the desktop. While these advances have radically changed the general purpose computing market, they are only beginning to be seen in the real-time market. Real-time distributed systems have been relying on raw computing power to satisfy performance requirements. Scalable multiprocessor architectures, while providing substantial processing power, do not often meet the demands of deterministic applications such as real-time simulation and control. The need for concurrent data sharing in multitasking, multiprocessor systems is the bottleneck in utilizing these technologies. This paper defines the architecture of an interfacing system for efficient coupling of processing modules for high performance multiprocessor applications. The Virtual Shared Memory Interconnect (VSI) minimizes data Stency between processors and provides process transparent communication for applications requiring shared data and cross-coupled interrupts between CPUs. This permits attainment of maximum available CPU bandwidth and brings a truly scalable architecture to the real-time arena. A commercial implementation of a 64-bit RISC CPU for real-time applications, configured around the VSI, is also describecd.