Obtaining J-K, D, and T excitation equations directly from state transition diagrams

This paper presents techniques for obtaining J-K, D, and T excitation equations for synchronous state machine designs directly from state transition diagrams. Classical designs using K-maps (Karnaugh maps) are time consuming to draw and difficult to use when large designs are involved. Computer tools are very valuable for assignments outside of the classroom, that is, for homework assignments, laboratory assignments, and special projects, but computers are not generally provided for student use on quizzes and exams. The techniques for obtaining flip-flop excitation equations presented in this paper apply to large or small designs. The excitation equations that are obtained usually need to be reduced prior to implementation. Although equation reduction is not the theme of this paper, some of the excitation equations will be obtained using algebraic reduction, K-map reduction, and computer tool reduction to allow comparisons to be made.