1. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 51 State Machine Implementation 10/2/20081ECE 561 - Lecture 5

2. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 52 Lecture Overview Another Example – a counting machine Another Example – Tail light controller 10/2/20082ECE 561 - Lecture 5

3. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 53 Counting Machine “Design a clocked synchronous state machine with two inputs, X and Y, and one output Z. The output should be 1 inputs on X and Y since reset is a multiple of 4, and 0 otherwise. There are 4 states 10/2/20083ECE 561 - Lecture 5

4. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 54 Construct a state table From word description construct a state table for the problem. 10/2/2008ECE 561 - Lecture 54

5. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 55 Do a state assignment Having state table pick a state assignment From here we can generate the excitation equations

6. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 56 Excitation Equations D1 = Q2 X’ Y + Q1’ X Y + Q1 X’ Y’ + Q2 X Y’ Z = Q1’ Q2’ D2 = Q1’ X’ Y + Q1’ X Y’ + Q2 X’ Y’ + Q2 X Y

7. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 57 Another Example Design a clocked synchronous state machine with one input X and two outputs, UNLK and HINT. The UNLK output should be 1 if and only if X is 0 and the sequence of inputs received on X the preceding seven clock ticks was 0110111. The HINT output should be 1 if and only if the current value of X is the correct one to move the machine close to being in the “unlocked” state (with UNLK = 1).

8. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 58 Create State Table Create a state table from the word description

9. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 59 Choose a state assignment To get transition/excitation table

10. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 510 Can use Karnaugh Map to get excitation equations D1 = Q1 Q2’ X + Q1’ Q2 Q3 X’. + Q1 Q2 Q3’ D2 = Q2’ Q3 X + Q2 Q3’ X D3 = Q1 Q2’ Q3’ + Q1 Q3 X’ + Q2’ X’.. + Q3’ Q1’ X’ + Q2 Q3’ X UNLK = Q1 Q2 Q3 X’ HINT = Q1’ Q2’ Q3’ X’ + Q1 Q2’ X. + Q2’ Q3 X + Q2 Q3 X’ + Q2 Q3’ X

11. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 511 For both examples Having the excitation and output equation can do the implementation in discrete logic or perform a schematic capture for FPGA tools such as XILINX or Altera.

12. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 512 Another example This is a example of a “real” deisgn The T-Bird Tail Light Problem

13. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 513 The Transistion Table Can again get the transition table

14. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 514 The State Diagram Can also draw a state diagram

15. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 515 Final steps Choose F/F type Choose a state assignment Develop the transition/excitation table for that state assignment Generate the equations

16. 10/2/0810/2/2008ECE 561 -ECE 561 - Lecture 516 Assignment 3 Carry through the remaining steps to get implementation and output equations and the circuit diagram for an implementation for the following state table.