
CHAPTER 10
Introduction to Synchronous State
Machine Design and Analysis
10.1 INTRODUCTION
Up to this point only combinational logic machines have been considered, those whose
outputs depend solely on the present state of the inputs. Adders, decoders, MUXs, PLAs,
ALUs, and many other combinational logic machines are remarkable and very necessary
machines in their own right to the field of logic design. However, they all suffer the same
limitation. They cannot perform operations sequentially. A ROM, for example, cannot
make use of its present input instructions to carry out a next-stage set of functions, and an
adder cannot count sequentially without