Current understanding of the PLA folding problem is limited to simple empirical evidence from studies of heuristic methods. This paper presents a theoretical approach through an analytical and statistical analysis. The problem is first mapped into a set theoretic model. Using a random selection heuristic as a basis, a probability density function (PDF) is derived for the expected number of folds under a set of simplifying assumptions. This PDF is derived in terms of the three fundamental properties of a PLA, r the number of rows, c the number of columns, and d the density. Empirical results obtained from folding thousands of randomly generated PLA's verify the accuracy of the derived probability density function. A technique is developed whereby the PDF can also be used to predict the size of optimal folding sets. A new folding heuristic is introduced which is shown to perform better than other heuristic algorithms in the literature, when applied to a set of randomly generated PLA's. This is the first folding heuristic to have an analytical basis for its expected results, as derived from the PDF function.

We consider the problem of automatic identification of parallel microoperations in a given straight-line microprogram. Earlier work on this problem generally falls into two categories. While some work is fairly general in that it can be applied to both monophase and polyphase systems, it does not guarantee optimality of the output. Work in the second category attempts to optimize the output, but is restricted in application to monophase microprograms.

The study of minicomputer systems in a laboratory environment has been considered by both Electrical Engineering [1], and Computer Science [2] departments. In a summary of the COSINE Committee report on Digital Laboratories, Booth [1] points out that since minicomputers are becoming an integral part of many industrial systems, it is mandatory that students be made aware of the principles of such systems. Further, Booth suggests that the best way to accomplish this is in a projects-oriented laboratory environment. We certainly agree with his statement that “A successfully completed project thus gives the student a sense of accomplishment that is hard to duplicate in any other educational situation.”

The combination of a large number of students and a rapidly developing discipline imposes considerable responsibilities on those charged with providing curricula in computer or computing science. Rather than philosophize about the nature of the discipline itself in this paper, we intend to discuss at a pragmatic level the problems we see at the present time in our own case, and the steps we are taking to resolve them.