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

Translate the following sentences into predicate logic, Translate the follo...

Translate the following sentences into predicate logic. Give as much structure as possible. Provide a translation key for each predicate letter and individual constant. In your tra

Example of blocking probability for the three stage network, A three stage ...

A three stage network is realized by using switching matrices of size p x s in stage 1, r x r matrices in stage 2 and s x p matrices in stage 3. Using the Lee's probability graph s

What are the different methods used for handling, What are the different me...

What are the different methods used for handling the situation when multiple interrupts occurs? 1) Vectores interrupts 2) Interrupt nesting 3) Simultaneous Requests.

What is datapool, A datapool is a source of variable test data that scripts...

A datapool is a source of variable test data that scripts can draw from during playback

Explain management information base variables, Explain MIB (Management Info...

Explain MIB (Management Information Base) variables. MIB is a set of named items which an SNMP agent knows. To control or monitor a remote computer, a manager should fetch or s

Integrated test result, COGNITIONS Mr. X exhibits a generally high-quali...

COGNITIONS Mr. X exhibits a generally high-quality level of cognitive and intellectual functioning, as evidenced by his performance on the MMSE-2 and WAIS-IV. His one weakness w

Difference between synchronous and asynchronous updates, What is the differ...

What is the difference between Synchronous and Asynchronous updates? A program asks the system to perform a particular task, and then either waits or doesn't wait for the task

Explain latex in matlab, Matlab already handles naturally easy LaTeX encodi...

Matlab already handles naturally easy LaTeX encodings that permit introducing Greek lettters or modifying the font size and appearance in plots.

What are the minimal cost and minimal risksolution, In binary representatio...

In binary representation there are some states that are believed to be never occurred because of some particular functionality of a given circuit. If zero output is assigned to suc

Determine the bandwidth requirement of a telephone channel, The bandwidth r...

The bandwidth requirement of a telephone channel is (A)  3 KHz                                      (B)  15 KHz (C)  5 KHz                                      (D)  25 KH

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