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

Write short note on quantization, Write short note on Quantization. Qua...

Write short note on Quantization. Quantization: This is the first step in PCM. The whole amplitude range of the modulating signal is divided in a number of standard levels term

How can we resize layout cells, Q. How can we Resize Layout Cells? To p...

Q. How can we Resize Layout Cells? To precisely design a page, you can set size of cells you add in a document. You can reposition cells in the page as well. 1.      Click o

Name the various display devices, Name the various Display devices Diff...

Name the various Display devices Different types of display devices are discussed along with the principles on which these work. The main display devices used with CAD systems

E brokerage facilitates search & retrieval of information, E Brokerage faci...

E Brokerage facilitates search & retrieval of Information The success factor of a brokerage is its ability to retain existing clients and to enhance their satisfaction by effec

State the hardware faults and softwate faults, State the hardware faults an...

State the hardware faults and softwate faults - protection against hardware faults could be to keep backups or use GFS; use of UPS (in case of power loss) and parallel system a

Explain memory write operation, Q. Explain Memory Write operation? Memo...

Q. Explain Memory Write operation? Memory write operation transfers content of a data register to a memory word M selected by the address. Presume that data of register R1 is t

Define device interface, Define device interface. The buffer registers ...

Define device interface. The buffer registers DATAIN and DATAOUT and the status flags SIN and SOUT are part of circuitry commonly called as a device interface.

Discuss about charles babbage in brief, Discuss about Charles Babbagein bri...

Discuss about Charles Babbagein brief Mechanism  for  advancing  or  reversing  of  control  card  were  allowed  therefore enabling execution of any desired instruction. In ot

State the structure of verilog code you follow, State the structure of Veri...

State the structure of Verilog code you follow? A good template for your Verilog file is shown below. // timescale directive tells the simulator the base units and precision

What are the methods for handling deadlocks, What are the methods for handl...

What are the methods for handling deadlocks?  The deadlock problem can be dealt with in one of the three ways:  a. Use a protocol to prevent or avoid deadlocks, make sure th

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