Sequential-State Digital Circuits

This chapter begins by discussing two sequential state problems. The first example drives home the point that the concept of a physical system changing state with time predates Shannon and Boole by centuries. The second example uses a more modern situation that just about everyone of driving age has encountered: the automated parking garage.

It then argues that the design of a sequential state digital machine is simply that of determining how to interconnect these individual latches so as to transition from state to state with the goal of accomplishing a desired task. The remainder of the chapter shows how the latch can be modified in several important ways to arrive at the practical logic element called the clocked, edge-triggered flip-flop, and concludes with the design of a specific machine.