The circuit given in Figure 4-52 is to be redesigned to cut its cost.

(a) Find the state table for the circuit and replace the state codes with single- letter identiiers. States 100 and 111 were unused in the original design.

(b) Check for and combine equivalent states.

(c) Make a state assignment such that the output is one of the state variables.

(d) Find the gate- input costs of the original circuit and your circuit, assuming that the gate- input cost of a D lip- lop is 14. Is the cost of the new circuit reduced?

Figure 4-52:

Transcribed Image Text:

X Clock Reset Y3 Y Y3 Y3- Y- D Y Y3 FD D D D C R C R C R Y b-Y -Y 6-Y b-Y N -Z