Explain about 4-bit adder-subtractor circuit, Computer Engineering

Assignment Help:

Q. Explain about 4-bit adder-subtractor circuit?

Subtraction operation on binary numbers can be obtained by succession of addition operations only it implies that to achieve subtraction A-B we can find 2's complement of B. This can be computed by 1's complemented and then adding 1 to it. So a common circuit can carry out addition and subtraction operation. A 4-bit adder subtraction circuit is displayed in figure below that is formed by employing XOR gate with each full adder. XOR gate with output 0 is for inspecting overflow.

2153_Explain about 4-bit adder-subtractor circuit.png

Figure: 4-bit adder-subtractor circuit

Control input 'x' controls operations it implies that if x =0 then circuit acts as an adder and if x =1 then circuit acts as a subtractor. The operation is summarized as below:

a. When x = 0, c = 0, output of all XOR gates would be same as corresponding input Bi where i = 0 to 3. So Ai and Bi are added by full adders providing Sum Si and carry Ci .

b. When x = 1 output of all XOR gates will be complement of input Bi where i =0 to 3 to that carry C0=1 is added. So circuit finds A plus 2's complement of B which is equal to A-B.


Related Discussions:- Explain about 4-bit adder-subtractor circuit

Explain the properties of hypercube, Q. Explain the properties of Hypercube...

Q. Explain the properties of Hypercube? Properties of Hypercube: Hypercube is both edge and node symmetric. The labels of any two neighbouring nodes vary in exactl

Define b2b - business to business, B2B - Business to Business  It is a...

B2B - Business to Business  It is a mode of conducting business among two or more companies over the Internet, rather than more traditional modes like as telephone, mail, and f

Concept of mouse, The concept of Mouse was designed by Douglas C. Engelbart...

The concept of Mouse was designed by Douglas C. Engelbart of Stanford Research institute and first Mouse was designed by Xerox corporation.  Mouse itself is a device that gives you

Capacity and access speed of hard disk, Capacity and access speed: PC ...

Capacity and access speed: PC hard disk drive capacity (measured in GB). The vertical axis is logarithmic, so the accurate line corresponds to exponential growth.  By using

Describe the role of software developers, Describe the role of Software dev...

Describe the role of Software developers Software developers have wide experience of tackling such issues. Students who develop software project spending days and nights strug

What do you mean by manual assembly, Q. What do you mean by Manual Assembly...

Q. What do you mean by Manual Assembly? It was an old method which required the programmer to translate every opcode in its numerical machine language representation by search

What does vuser_init action contain, Vuser_init action haves procedures to ...

Vuser_init action haves procedures to login to a server.

Explain 32 to 1 multiplexer tree, Why is Multiplexer Tree needed? Draw ...

Why is Multiplexer Tree needed? Draw the block diagram of a 32:1 Multiplexer Tree and explain how input is directed to the output in this system. Ans. One of the possible

Determine the begin - end keywords, Determine the begin - end keywords ...

Determine the begin - end keywords Group several statements together. Cause the statements to be evaluated sequentially (one at a time) -> Any timing within sequential group

What is register set, What is Register Set Register Set:  Register set ...

What is Register Set Register Set:  Register set is used to keep immediate data during the implementation of instruction. This area of processor having of various registers.

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