An algorithm for minimizing read only memories for machine control

This paper describes an algorithm for minimizing the storage required of a Read Only Memory that is going to be used as the control element for a digital machine. The technique is based upon the fact that not all sub-commands are required in all words so that bits of the memory may be time shared between subcommands. The algorithm provides a means for determining what sub-commands should share a common set of bits. The algorithm is essentially one of exhaustive evaluation but it is one that directs you toward the solution rather than one which randomly tries all possible solutions and chooses the best. In addition certain bounds on the "size" of the solution are derived and these in turn eliminate a large segment of the possible solution set from consideration. Finally, the algorithm is quite iterative and as such lends itself readily to implementation of a digital machine.