Techniques for improved testability in the IBM ES/9370 system

Abstract

The authors discuss three techniques used in the IBM ES/9370 series of processors to improve the testability, and hence the quality levels, of card assemblies. First they investigate the testing requirements and challenges presented by a nonvolatile static RAM and how they were met. Then they introduce a method which uses flush-through logic to provide improved access to array components. Next, the authors discuss how a compare circuit can be used to reduce I/O (input/output) requirements when testing an array. These algorithms were successfully implemented using programming Language for Testing (PLT). Background information and a detailed methodology for each of the techniques are provided.<>