Multiprocessor simulation of neural networks with NERV

A general-purpose simulation system for neural networks is computationally very demanding. This paper presents some estimations of the computing power required, the necessary interconnection bandwidth, and the requisite memory size. Next, the hardware architecture of the NERV multiprocessor system is derived that fulfills these requirements. Up to 320 processors 68020 are used in a single VME crate together with a Macintosh II as a host computer. This set-up provides a computing power of 1300 MIPS together with a friendly graphical user interface. To support the simulation of arbitrarily interconnected networks and of asynchronous update models, the VME bus has been extended by a broadcast feature and a global max finder. The software architecture is outlined. It consists of system software, utilities, and application software.