Expalin johnson counter, Computer Engineering

Assignment Help:

Write short note on the Johnson counter.

Ans:

 Johnson Counter: It is a synchronous counter, where all flip-flops are clocked concurrently and the clock pulses drive the clock input of all the flip-flops together therefore there is no propagation delay. Fig.(a) demonstrates the circuit of Johnson counter. In case of the  D  input  of  FF0  is  driven  by  Q‾ output  of  FF3, that is, the complement of the output of the final flip flop is fed to the D of FF0. Feedback of this arrangement generates the sequence of states illustrated in Table no.1. The 4 bit sequence has a total of 8 states (there is n bit sequence will have 2n states). Therefore an n bit Johnson counter will have a modulus of 2n.

The Q output of all stage feeds the D input of next stage. Although the Q‾ output of the final stage feeds the D input of primary stage. The counter fills up along with 1's from left to right and after that fills up 0s again as demonstrated in Table no.2. Fig. (b) Demonstrates the wave shapes/timing diagram of 4 bit Johnson counter.

563_Logic Diagram of Johnson counter.png

Fig.(a) Logic Diagram of Johnson counter

Clock Pulse

Q0

Q1

Q2

Q3

0

0

0

0

0

1

1

0

0

0

2

1

1

0

0

3

1

1

1

0

4

1

1

1

1

5

0

1

1

1

6

0

0

1

1

7

0

0

0

1

Table no.1 Sequence of states of 4 bit Johnson Counter

2108_Timing Diagram of 4-bit Johnson Counter.png

Fig.(b) Timing Diagram of 4-bit Johnson Counter


Related Discussions:- Expalin johnson counter

Develop a plan to apply theory of constraints, 1. The Goal: Do you think th...

1. The Goal: Do you think that this is an operational methodology or a philosophy? Please explain. 2. How to apply Constraint Management to a Production Facility? How about to a

How do you ensure that our records are scanned accurately, How do you ensur...

How do you ensure that our records are scanned accurately? Not only do we have a highly trained and capable staff, we also have quality controls in place to make sure your reco

Control section in computer system, CONTROL SECTION: The control sectio...

CONTROL SECTION: The control section directs the flow of traffic (operations) and data. Also it maintains order within the computer. The control section chooses one program sta

What is pci bus, What is PCI bus? The Peripheral component interconnect...

What is PCI bus? The Peripheral component interconnect(PCI) bus is a standard that handles the functions found on a processor bus but in a standardized format that is independe

Explain the race condition, Explain the Race Condition The situation wh...

Explain the Race Condition The situation where various processes access - and manipulate shared data concurrently. The final value of the shared data relies upon which process

C#, I have assignment about writing code in c# language this code to contro...

I have assignment about writing code in c# language this code to control the leds in the circuit board ..any idea

Amdahls law - calculate speed up performance, To calculate speed up perform...

To calculate speed up performance various laws have been developed. These laws are discussed here.  Amdahl's Law Remember, the speed up factor helps us in knowing the relat

Important steps of the boot process, Question: Computer forensic examin...

Question: Computer forensic examiners should be concerned with at least two important settings stored in RTC/NVRAM, which is accessed by the BIOS software most often called Set

CPE, WHAT IS CPE

WHAT IS CPE

Explain the fixed logic versus programmable logic, Explain the Fixed Logic ...

Explain the Fixed Logic Versus Programmable Logic? The Logic devices can be classified into two broad categories - fixed and programmable. The same as the name suggests, the ci

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd