Bit manipulation techniques, Computer Engineering

Assignment Help:

  We can also use the logical operators to numbers directly and  perform simple bit manipulation . The operators are

    &  Bitwise AND
    |  Bitwise OR
    ^  Bitwise exclusive or 
    ~  Bitwise one's complement i.e. NOT
    <<  Left shift
    >>   Right shift

Example
  A 8 bit number represents a coded function, bit  3-4 describes the operation to be performed on the number in bits 0- 2 and 5-7  the function i.e. 
 
    00    Add
    01    Subtract
    10     Divide
    11    Multiply
 
  Write a Program to extract the number and operation

Answer
We need to extract the bits 3-4, the answer is bit operators 
 
    Assume number is in the variable A i.e.  11011011
 
    Mask off the first number i.e. bit 0-2
    num1 = a & 0x07;        11011011 and
                00000111
                00000011
    
    Mask off the second number i.e. bit 5 -7
    num2 = a & 0xe0;        11011011 and
                11100000
                11000000
 
    We need to shift num2 down by 5 places i.e.
    num2 = num2 >>5;
                00000110

This could be done in one instruction i.e.
    num2 = (a & 0xe0) >> 5;
 
  Mask off the operation bits i.e. bit 4-5
    operation = (a & 0x18) >> 3;
 
  We can then use the switch statement to select each operation
  switch(operation)
  {
  case 0:  
    total = num1+num2;
    break;
  case 1: 
     total = num1-num2;
    break;
  case 2:  
    total = num1/num2;
    break;
  case 3:  
    total = num1*num2;
    break;
  }
Hence the entire program is 
  #include
  void main()
  { 
  char prompt;
  /*Author : Mr James Mc Carren 
  Company: Staffordshire University 
   Date: 26th August 2012 
  Version 1.0 
   Function : To show bit manipulation
   Modifications:   none*/
  int num1,num2,operation,total,a;
  printf("Please enter in the number\n\r");
  scanf("%x",&a);
  num1 = a & 0x07;  
  num2 = (a & 0xe0) >> 5 ;
  operation = (a & 0x18) >> 3;
  switch(operation)
  {
  case 0:   total = num1+num2;
    break;
  case 1:  total = num1-num2;
    break;
  case 2:  total = num1/num2;
    break;
  case 3:  total = num1*num2;
    break;
  }
  printf("The total is %d\n\r",total); 
  printf("Press and key to exit \n\r");
  scanf("\n%c",&prompt);
  }


Related Discussions:- Bit manipulation techniques

Operating system., what is the minimum number of page faults for an optimal...

what is the minimum number of page faults for an optimal page replacement strategy?

Write the game using writing functions, The year is 2199. For many generati...

The year is 2199. For many generations, the robotic Cyleth have faithfully served humanity. However, under the direction of the computerized superintelligence Skyweb, they have tur

Define the actions a process take upon receiving a signal, Define the vario...

Define the various actions a process might be take upon receiving a signal? There are various actions a process might be take upon receiving a signal here are three different d

Why is packet switching important, Why is packet switching important? Give ...

Why is packet switching important? Give at least two reasons. Packet switching is significant due to the following two purposes: 1. A sender and the receiver require coordin

Implement the concept of true and radix minus one complement, Q. Develop a...

Q. Develop a program to implement the concept of true and radix minus one complement. Program should ask for radix and two numbers from that radix. For that two numbers program

What is the dissimilarity between dynamic strain aging, Q. What is the diss...

Q. What is the dissimilarity between dynamic strain aging and strain aging? Answer:- Strain aging could be explains as "normal wear and tear" or the fatigue that is experi

Write a short note on mmx technology, Write a short note on MMX technology....

Write a short note on MMX technology. MMX (Multimedia extensions) technology adds 57 new instructions to instruction set of the Pentium - 4 microprocessors. MMX technology also

Counter, mod12 counter connection diagram

mod12 counter connection diagram

Algorithmic complexity theory, Algorithmic Complexity theory: Moreover...

Algorithmic Complexity theory: Moreover a similar situation occurs in broad to specific ILP systems when the inference rules are deductive thus they specialize. So at some sta

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