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

What is multiplicity, What is multiplicity? Multiplicity is applied to ...

What is multiplicity? Multiplicity is applied to attributes for data base application. Multiplicity for an attribute specifies the number of possible value for every instantiat

Explain non-pre-emptive algorithms, Explain non-pre-emptive algorithms?   ...

Explain non-pre-emptive algorithms?   Non preemptive algorithms: In this algorithm a job is provided to CPU for execution as long as the job is non-completed the CPU cannot

What are the simplest way to restrict the users, What are the simplest way ...

What are the simplest way to restrict the users The simplest way to restrict the users to peek inside the internals of the Web site is to use firewalls, where the information c

Explain booth''s multiplication algorithm, Computer Organization 1. Dr...

Computer Organization 1. Draw a flowchart of a Booth's multiplication algorithm and explain it. 2. What is the concept of memory interleaving? 3. Explain virtual memory? Expla

How to fix an asic-based design from easiest to most extreme, How to fix an...

How to fix an ASIC-based design from easiest to most extreme? There are different ways to fix an ASIC-based design as given below: Initially, assume some reviews fundamentally.

What is virtual memory, Virtual Memory is a way of extending a computer's m...

Virtual Memory is a way of extending a computer's memory by using a disk file to replicate add'l memory space. The OS remain track of these add'l memory addresses on the hard disk

Which rule is used for the expansion of nested macro calls, The expansion ...

The expansion of nested macro calls done by using of? Ans. LIFO rule is used for the expansion of nested macro calls.

What is the purpose of the cpu, Problem 1 a) What is the purpose of th...

Problem 1 a) What is the purpose of the CPU and what can the CPU perform. b) Name the two most common types of software and briefly illustrate each one. c) The CPU con

Functionality of hyper thread processor, Hyper-threading works by duplicati...

Hyper-threading works by duplicating those sections of processor that kept the architectural state-but not duplicates the main implementation resources. This allows a Hyper-threadi

Engineering and scientific software, Engineering and Scientific Software ...

Engineering and Scientific Software Engineering  and  Scientific  software  has  been  characterized  with "number crunching" algorithms. Application starts from astronomy t

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