384 ~ Solutions (or Hints) to Chapter-end Exercises
TABLE A3.7 Mealy Machine of Exercise 3.11
Present state
Next state
a = 0
a = 1
state
output
state
output
Q1
0
q2
1
q3
1
q2
1
q2
1
q1
0
qo
1
q3
1
3.12 qj is associated with 1 and q2 is associated with 0 and 1. Similarly, q3
is associated with 0 and 1, whereas q4 is associated with 1. The state
table with new states qj, Q20, Q2j, q30, Q3l and q4 is defined by Table A3.8.
TABLE A3.8 State Table for Exercise 3.12
Present stare
Next state
a = 0
a = 1
state
output
state
output
q1
0
q20
0
q4
1
q4
1
q4
q4
1
q21
q31
1
q21
1
q31
1
Q30
0
q1
1
The revised state table is defined by Table A3.9.
TABLE A3.9 Revised State Table for Exercise 3.12
Present state
Next state
a = 0
a = 1
output
-7
qo
q1
Q20
0
q1
q1
q20
1
q20
q4
q4
0
q21
q4
q4
1
q30
q21
q31
0
q31
q21
q31
1
q4
q30
q1
1
3.13 The Mealy machine is described by Fig. A3.3.
a,Even
a,Odd
H 1,Odd H
~
1, Even
Fig. A3.3 Mealy machine of Exercise 3.13.