LOGIC14_r2

# LOGIC14_r2 - Chapter 14 Derivation of State Graphs Tables...

This preview shows pages 1–10. Sign up to view the full content.

Microwave & Communication Lab. Chapter 14 Derivation of State Graphs & Tables

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Microwave & Communication Lab. The detector will examine a string of 0’s & 1’s applied to the X input and generate an output Z=1 only when a prescribed input sequence occurs. In this network, any input sequence ending in 101 will produce an output Z=1 coincident with the last 1. i.e., Z=1 iff X=101. § Sequence Detector
Microwave & Communication Lab. A typical input and corresponding output X= 0 0 1 1 0 1 1 0 0 1 0 1 0 1 0 0 Z= 0 0 0 0 0 1 0 0 0 0 0 1 0 1 0 0 time: 0 1 2 3 4 5 6 7 8 9 1011 12131415

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Microwave & Communication Lab. Mealy network: X/Z 1. Start the network in a reset state designated S 0 . 2. If a “0” input is received, the network can stay in S 0 since the input sequence we are looking for does not start with “0”. 3. If a “1” is received. We must go to a new state S 1 to remember that the first input in the desired sequence has been received.
Microwave & Communication Lab. 4.When in state S 1 , if we receive a “0”, the network must change to a new state S 2 to remember that the first two inputs of the desired sequence (10) have been received. If a “1” is received in S 2 , the desired input sequence (101) is complete and the output should be 1. When in state S 1 , if a “1” is received, we can stay in S 1 since the sequence is simply restarted. 5.If a “0” occurs in state S 2 , two “0”s are received and we must reset the network to state S 0 .

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Microwave & Communication Lab. So, the state graph for sequence detector.
Microwave & Communication Lab. State Table Present Next State Present Output State X=0 X=1 X=0 X=1 S 0 S 0 S 1 0 0 S 1 S 2 S 1 0 0 S 2 S 0 S 1 0 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Microwave & Communication Lab. Since one FF can have only two states, two FFs are needed to represent the three states. Designate the two FFs as A&B. Let A=0, B=0, state S 0 A=0, B=1, state S 1 A=1, B=0, state S 2 therefore, A + B + Z A B X=0 X=1 X=0 X=1 0 0 0 0 0 1 0 0 0 1 1 0 0 1 0 0 1 0 0 0 0 1 0 1
Microwave & Communication Lab.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern