A rapid-prototyping environment for digital-signal processors

A description is given of the Diodes system, a complete rapid prototyping, debugging, and test environment including both hardware and software, for the design of digital-signal-processing chips. The test circuitry in Diodes differs from that in many systems, including those based on boundary scan, by offering full-speed circuit testing and the observation of internal nodes during real time. Diodes also achieves nearly 100% fault coverage because chips are composed of numerous chunks, each of which is tested exhaustively. The discussion covers the high-density interconnection technology and the concepts on which Diodes is based, two types of chips that have been designed, fabricated, and tested for Diodes: module assembly and fabrication; synthesis software; on-chip testing; Diodes test circuitry; test modes; and hardware and software debugging. Diodes is compared with other testing approaches and other rapid prototyping systems.<>