# Evaluate 2’s complement of 8 bits including sign bit. iii) Add 64 and 61- IGNOU MCA Assignment 2015 – 16

By | September 1, 2015

MASTER OF COMPUTER APPLICATIONS

Course Code : MCS-012
Course Title : Computer Organisation and Assembly Language Programming
Assignment Number : MCA(I)/012/Assignment/15-16
Maximum Marks : 100
Weightage : 25%

Perform the following arithmetic operations using binary signed 2’s complement notation for integers.

You may assume that the maximum size of integers is of 8 bits including the sign bit. (Please note that the numbers given here are in decimal notation)

i) Add – 128 and 120

ii) Subtract 124 from –99

Please indicate the overflow if it is occurs. Also write how you have identified the overflow.

First, we have to represent the number in binary notation

The sign of a binary number is represented by 0 as plus and 1 as minus

Sign bit                                 7 -bits

 0 / 1

Now, Binary value of the given number

+64 – 1000000

+61 – 0111101

+64:-

Sign bit                                 7 -bits

 NA 0 1 0 0 0 0 0 0

+61:-

Sign bit                                 7 -bits

 NA 0 0 1 1 1 1 0 1

Sign bit                                 7 -bits

+64:-

 NA 0 1 0 0 0 0 0 0

+61:-

 NA 0 0 1 1 1 1 0 1

+256 :-

Carry bit

 NA 1 0 0 1 0 0 0 0 1

Overflow condition occurred.

The magnitude has been overflowed into sign bit and sign into carry the given 8-bits are not sufficient for the result of the magnitude.