Issue No. 04 - April (1974 vol. 23)
C. Montangero , Istituto di Elaborazione dell'Informazione del C.N.R., Pisa, Italy, and with Istituto di Scienze dell'Informazione, University of Pisa
This paper illustrates an algorithm for finding a read-only memory (ROM) specification, optimal in the sense that it results in a minimum ROM bit dimension, starting with an instruction set description which employs acyclic directed graphs. The algorithm selects (by a tabular technique) a descriptive graph subset, shown to be sufficient; then it performs a heuristically guided search among possible solutions generated by the graphs in the subset. The algorithm works for instructions which are such that a microevent occurs at most once in a single instruction; some results apply to the general case as well.
Balanced row, compatibility class, level assignment, prime descriptive graphs, prime dominance table, ROM specification.
C. Montangero, "An Approach to the Optimal Specification of Read-Only Memories in Microprogrammed Digital Computers," in IEEE Transactions on Computers, vol. 23, no. , pp. 375-389, 1974.