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

What is ''preemption'' program, Program 'preemption' is? Ans. Forced de...

Program 'preemption' is? Ans. Forced de allocation of the CPU from a program that is executing on the CPU is called preemption program.

What are the disadvantages of fcfs scheduling algorithm, What are the disad...

What are the disadvantages of FCFS scheduling algorithm as compared to shortest job first (SJF) scheduling? Disadvantages: (i) Waiting time can be huge if short requests w

C++ program on pebble merchant, how to solve pebble merchant problem.? codi...

how to solve pebble merchant problem.? coding for it..!

Features and utilities available in java, Explain the features and utilitie...

Explain the features and utilities available in java, which makes it suitable for developing e-commerce applications.     1.  In a network, the transmission of passive informati

#, advantages of dda line algoritm

advantages of dda line algoritm

What the first part of the address identifies in e-mailbox, The first part ...

The first part of the address in electronic mailbox identifies? The first part of address in E-Mail identifies the user's mail box.

Calculate width and height of the grid, Given a cell, we must determine its...

Given a cell, we must determine its neighbouring cells i.e. those with which it shares a wall. The cells with an x are the neighbours of the cell c. Write the function getneighbour

Array processing, Array Processing We have seen that for performing vec...

Array Processing We have seen that for performing vector operations, the pipelining concept has been taken. There is another method for vector operations. If we have an array o

How are connections managed in orbix connect, The Orbix Connect resource ad...

The Orbix Connect resource adapter is packaged as a standard J2EE Connector Architecture resource adapter archive (RAR) file, corbaconn.rar. The corbaconn.rar file having all the c

Explain csmsginterface() function with predefined protocol, Explain CSMsgIn...

Explain CSMsgInterface() Function with Predefined Protocol  A REQUEST structure is created for each message sent to the server. Messages passed to CSMsgInterface() as *dataMSG

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