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

Explain hypertext transfer protocol, Explain Hypertext Transfer Protocol. ...

Explain Hypertext Transfer Protocol. HTTP is used mainly in today's society like a set of rules for exchanging files (graphic images, text, sound, other multimedia files or vid

Explain increments and skips subsequent instruction, Q. Explain Increments ...

Q. Explain Increments and skips subsequent instruction? Increments A and skips subsequent instruction if the content of A has become 0. This is a complex instruction then requi

Define the aims of program generation activity, Program generation activity...

Program generation activity aims at? Ans. At automatic generation of program the program generation activity aims.

Describe the importance of micro-programming, Question: (a) Describe t...

Question: (a) Describe the importance of Micro-Programming and point out one area where Micro-Programming is extensively used. (b) Below is a diagram of an 8086 processor.

Explain about control memory organization, Q. Explain about Control Memory ...

Q. Explain about Control Memory Organization? One of the simplest ways to organize control memory is to organize micro-instructions for different sub cycles of machine instruct

Compare the cocomo model with the detailed cocomo model, Compare the basic ...

Compare the basic COCOMO model with the detailed COCOMO model. COCOMO having of a hierarchy of three increasingly detailed and accurate forms. -  Basic COCOMO - is a stati

Determine the benefits of developing prototype, Determine the benefits of d...

Determine the benefits of developing prototype According to SOMM [96] benefits of developing prototype are as following:  1.  Communication gap between clients and software

How do you make an append query, Append query can be used if you would like...

Append query can be used if you would like to add new rows of data to an already active table. The process of making an append query follows these steps they are. ? Basic step

Structure of 8086 cpu, 8086 microprocessor comprises two independent units:...

8086 microprocessor comprises two independent units:  1.  Bus Interface unit 2.  Execution unit Please refer to Figure below. Figure: The CPU of INTEL 8086 Microp

Explain sr latch with nand gate, Explain SR Latch with NAND Gate? SR La...

Explain SR Latch with NAND Gate? SR Latch has two useful states: Set state, when output Q=1 and Q'=0. Reset state, when output Q=0 and Q'=1.Output Qand Q' are normally

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