1. CS 140L Lecture 7 Transformation between Mealy and Moore Machines Professor CK Cheng CSE Dept. UC San Diego

2. Outlines Framework Procedure Example: Transform Example: State Diagram Example: Output Sequence

3. Transform from Mealy to Moore Machine Mealy Machine: y(t) = f(x(t), s(t)) Moore Machine:y(t) = f(s(t)) s(t+1) = g(x(t), s(t)) C1C2 CLK x(t) y(t) Mealy Machine C1C2 CLK x(t) y(t) Moore Machine s(t) 3

4. Transform from Mealy to Moore Machine 1) For each NS, z = S i,y j create a state S i (j) 2) For each new state S i (j), repeat the row PS = S i 3) Replace NS, z = S i,y j with state S i (j). Set output z = y j for row PS = S i (j) Algorithm Input: State Table of Mealy machine

5. Mealy Machine: Example PS A B 00 A,0 A,1 01 A,1 B,0 10 B,0 (x,y) (NS, z) PS A0 A1 B 00 A0 A1 01 A1 B Moore Machine: 10 B (x,y) z 0 1 0

6. Mealy Machine A0/0 A1/1 B/0 10 00 10 01 00 01 A 10/0 B 00/1 00/0, 01/1 10/0, 01/0 Moore Machine State Diagram

7. Timing Diagrams Time step x y S z S z 0 A 0 A0 0 1 0 1 A 1 A0 0 2 1 0 A 0 A1 1 300B1B0300B1B0 4 0 1 A 1 A1 1 5 0 1 A 1 A1 1 Mealy Moore The output shifts by one clock from Mealy to Moore machine A A1 1