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

Zero address instruction format, Zero address instruction format is used fo...

Zero address instruction format is used for  (A) RISC architecture.      (B) CISC architecture.  (C) Von-Neuman architecture.   (D) Stack-organized architecture.

Explain the working of a half subtractor, With the help of a truth table ex...

With the help of a truth table explain the working of a half subtractor. Draw the logic diagram using gates. Ans: Half Subtractor: For the subtraction of B (subtrahend) f

State the advantages off-the-shelf, State the advantages Off-the-shelf ...

State the advantages Off-the-shelf -  tends to be less expensive as development costs can be spread over many users -  can be more sophisticated as large sales bring in c

Role of internet in progressing sciences, Ask question #Minimum 100 wordswh...

Ask question #Minimum 100 wordswhat is the .role of internet in progressing sciences accepted#

Problems for decision tree learning, Appropriate Problems for Decision Tree...

Appropriate Problems for Decision Tree Learning : However remember there that is a skilled job in "AI" to choose exactly the right learning representation ormethod for a parti

Continuous or discrete - artificial intelligence, Continuous or Discrete - ...

Continuous or Discrete - artificial intelligence: The behaviour of the coming data in from the environment will change how the agent should be programming. In particular, the

Compute the coefficient for classifier, Consider the data with categorical ...

Consider the data with categorical predictor x 1 = { green or red } and numerical predictor x 2 and the class variable y shown in the following table. The weights for a round

Determine the output waveforms for and and or gates, The voltage waveforms ...

The voltage waveforms shown in given fig. are applied at the inputs of 2-input AND and OR gates. Determine the output waveforms. Ans. The Output waveforms for AND and O

Communications between the user and the server, Communications between the ...

Communications between the user and the server A significant enhancement was achieved when communications between the user and the server was sent in encrypted form and later

Manipulating logical expressions, Digital circuits also manipulate logicale...

Digital circuits also manipulate logicalexpressione.g. IF account is in credit THEN allow phoneto make calls.So a digital circuit must determine if somethingis TRUE or FALSE. Norma

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