The Design ProcessI.Read the statement of the problem.A.Settle the requirements of the specification.B.Determine the appropriate model. II.Model the system.ACreate a state transition diagramA.Create a state-transition diagram.B.Create a state-transition table.III.Eliminate redundant states.IV.Make a state assignment.A.Apply Armstong’s method to obtain maximal adjacencies ORB.Use a one-hot code state assignmentVRealize the circuitV.Realize the circuit.A.Select the flip-flop type.B.Use the appropriate excitation table to derive logic equations.C.Draw the circuit diagram for the logic equations.D.Simulate the circuit to judge its effectivenesseffectiveness.E.Evaluate the cost and speed of the realization.
State ReductionWe will consider the motivation for state reduction through a design example.A sequential circuit has two inputs xaand xb, and two outputs, zaand zb. The bits of xaand xbrepresent two unsigned binary numbers of arbitrary precision, aand b respectively.The bits of aand bare shifted into the sequential circuit on xaand xbin synchronicity with the system clock, higher-order bits first. At the time that the lowest-order bits are present as inputs on xaand xb, h f h l f llthe outputs of the sequential circuit are as follows:za= 1 if and only if a ≥b.zb= 1 if and only if b ≥a.xa100111010010xb101001010001a124919390124918b1251020410124817Za110000111111zb111111111100
This preview has intentionally blurred sections.
Sign up to view the full version.