How does the computer execute a program, Computer Engineering

Assignment Help:

Let's attempt to answer a fundamental question: 'How does the Computer execute a Program?' Let's describe this with the help of an example from higher level language domain.

Problem:  Write a program to add two numbers.

A sample C program (Assuming two fixed values of numbers as a = 5 and b = 2)

1.  #include < stdio.h >

2. main ()

3.    {

4.  int a =5, b=2, c;

5. c= a+b;

6. printf ("\n The added value is: % d", c);   

7.           }

Program at line 4 states variables which will be equal to 3 memory locations that are a, b and c.  At line 5 these variables are added along with at line 6 value of c is printed.

However how will these instructions be executed by CPU? First you have to compile this program to convert it to machine language. Though how will the machine instructions look like? Let's suppose a hypothetical instruction set of machines of a size of 16 binary digits (bits) data and instructions. Each one of the instruction of machine comprises two components: (a) Operation code which specifies the operation which is to be performed by instruction and (b) Address of operand in memory on that given operation is to be performed.

Let's further presume that size of operation code is supposed to be of six bits consequently rest 10 bits are for address of operand. Also the memory word size is presumed to be of 16 bits. Figure below shows instruction and data formats for this machine.  To simplify our discussion let's present operation code employing Mnemonics such as ADD, LOAD, STORE and signed decimal values for data and decimal values of operand addresses. 

756_How does the Computer execute a Program.png


Related Discussions:- How does the computer execute a program

Running time - metrics for performance evaluation, Running Time - Metrics f...

Running Time - Metrics for performance evaluation: Running time is amount of time consumed in execution of an algorithm for a provided input on N-processor based parallel comp

Explain the advantages of object oriented analysis design, Advantages of Ob...

Advantages of Object oriented analysis design The OO approach inherently makes every object a standalone component which can be reused within specific stat problem domains we

Give the example of first come first served scheduling, Consider  the  foll...

Consider  the  following set of jobs with  their  arrival  times,  execution  time  (in minutes), and deadlines. Job Ids Ar r ival Time E

Explain the modularity of object oriented analysis, Explain the Modularity ...

Explain the Modularity of Object oriented analysis Modularity is closely attached to encapsulation; you may think of it as a way of mapping encapsulated abstractions into phys

Catch output from child tasks, Q. Catch output from child tasks? ...

Q. Catch output from child tasks? int pvm_catchout( FILE *ff ) Catch output from child tasks. ff is file descriptor on which we write collected output. The defau

Explain bottom up parsing, Explain Bottom up parsing. Bottom up pars...

Explain Bottom up parsing. Bottom up parsing: This parse attempts to increase syntax tree for an input string by a sequence of reduction. If the input string can be decreas

What is relational database, What is relational database? Relational da...

What is relational database? Relational database has data that is perceived as tables. A relational DBMS manages tables of data and associated structures that enhances the func

What is machine.config, What is Machine.config?  Machine configuration ...

What is Machine.config?  Machine configuration file: The machine. config file contains settings that apply to the whole computer.  The machine.config, which can be found in the

What is electronic data interchange, What is Electronic Data Interchange? ...

What is Electronic Data Interchange? Electronic Data Interchange (EDI): It is used by organizations for transactions which arise on regular basis to a pre-found format.

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