Controlling and programming the SPHINX multi-SIMD pyramid machine

A control scheme with a very limited overhead for SPHINX, a cellular pyramidal machine primarily designed for image-processing applications, is presented. It is organized as a set of stacked layers of decreasing size interconnected according to a dual network: a mesh-based interneighbor interconnection network within a layer and a binary tree between adjacent layers. The SPHINX processing element relies on bit serial operations and communications. It is formed of an arithmetic and logic unit with enhanced data transfer capabilities, a 256-bits local memory, and a set of special-purpose registers. A low-overhead interlayer method to synchronize communication of independently controlled single-instruction multiple-data (SIMD) processor meshes is presented. It is shown how it can be used to provide multitasking within a mesh to allow opposite data flow to cross safely. Related programming concepts for multi-SIMD machines-control transmission-are presented