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 are the properties of e-cash, What are the properties of E-cash? ...

What are the properties of E-cash? Properties: a. Monetary Value: It must be backed through either cash, bank –certified cashier’s cheque and authorized credit cards.

What is paging unit, Paging Unit Paging mechanism functions with 4K -...

Paging Unit Paging mechanism functions with 4K - byte memory pages or with a new extension available to Pentium with 4M byte-memory pages. In the Pentium, with the new 4M-byt

IEEE802, 1. (a) Given a baseband bus with station 1 located at 10m, station...

1. (a) Given a baseband bus with station 1 located at 10m, station 2 located at 1000m, and station 3 located at 1010 meters (see diagram above). If the data rate of the bus is 10 M

Explain difference between macro call and macro expansion, Explain differen...

Explain difference between macro call and macro expansion. Macro expansion: While a macro name is used along with a set of actual parameters this is replaced through a code g

Explain data rates in public switched telephone network, Explain data rates...

Explain data rates in public switched telephone network. Data rates in PSTNs : A voice channel in a public switched telephone network is band restricted with a nominal bandwid

Dbms, what is cascading rolback?

what is cascading rolback?

Engineering applications, Engineering Applications A few of the enginee...

Engineering Applications A few of the engineering applications are: Airflow circulation over aircraft machinery, Simulations of simulated ecosystems. Airflow c

Electing neil, ELECTING NEIL : The response for this is, of course. In...

ELECTING NEIL : The response for this is, of course. In this case, we considered the point of the search or researching is to find an artifact  -  a word which is an anagram o

What is time slicing, What is time slicing? With this technique each pr...

What is time slicing? With this technique each program runs for a short period known as a time slice, and then another program runs for its time slice and so on.

For which class address 192.5.48.3 belogs, Address 192.5.48.3 belongs to? ...

Address 192.5.48.3 belongs to? Address 192.5.48.3 belongs to class C.

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