Introduction - mrgict.files.wordpress.com€¦ · Web viewBy the end of this section you should be able to describe: describe the main features of operating systems – for example,

F453 Computer Hardware Unit

ContentsIntroduction...........................................................................................................1About.....................................................................................................................1Functions of Operating Systems (3.1)....................................................................2

Symbols used in this book:.................................................................................2A) Features of Operating Systems....................................................................3Fetch Execute Cycle...........................................................................................4B) Interrupt Handling..........................................................................................5C/D) Memory Management.................................................................................6Extension Questions:..........................................................................................9F) File Management..........................................................................................10Boot Files..........................................................................................................10ROM and the Boot File......................................................................................11File Management..............................................................................................11File Allocation Tables........................................................................................12

The Directory Table.......................................................................................12End of Unit Recap................................................................................................13

Additional Notes...............................................................................................13

IntroductionThis book is designed to teach the F453 unit of the OCR Specification. I have used the marking criteria from the OCR Scheme of Work to highlight the areas that you need to know. You should use this book alongside the classroom activities to complete.

IT IS NOT a full and complete guide, in a number of places you will see extension tasks which are designed for higher grades to make sure you thoroughly understand a topic, if you want a grade higher than a B, I suggest you do these.

About

Mr B Gristwood, 2012 P a g e | 1


Functions of Operating Systems (3.1)

By the end of this section you should be able to describe:

A. describe the main features of operating systems – for example, memory management, scheduling algorithms;

B. explain how interrupts are used to obtain processor time and how processing of interrupted jobs may later be resumed, (typical sources of interrupts should be identified and any algorithms and data structures should be described);

C. define and explain the purpose of scheduling, job queues, priorities and how they are used to manage job throughput;

D. explain how memory is managed in a typical modern computer system, (virtual memory, paging and segmentation should be described along with some of the problems which could occur such as disk threshing

E. describe spooling, explaining why it is used;F. describe the main components of a typical desktop PC operating system,

including the file allocation table (FAT) and how it is used, and the purpose of the boot file.

Symbols used in this book:

Whenever you see this image it is a dictionary definition or keyword you need for this course

When you see this image, it requires you to find definitions from the internet, but also describe what this term means in your own words/full sentences.

When you see this image, this is a class activity that you must complete, usually a diagram and a definition.

This is an extension task. It is optional, but will help you in the exam



A)Features of Operating Systems

All computers need an operating system to run. After looking at the powerpoint, complete the tasks below.

Define: What is an Operating System

Define: The main features of an operating system

Revision: types of Operating System. Use the worksheet to complete the descriptions of the different types of operating system. Different operating systems can be used for different tasks, you can’t use Windows for everything, it is important to remember that.

Operating System Type

Description

Batch ProcessingInteractive ProcessingReal TimeNetworkFile ManagementDisk Operation SystemSingle UserMulti ProgrammingMulti UserMulti TaskingDistributed



Fetch Execute Cycle

All Operating Systems have to adhere to the Fetch Execute cycle of the processor. The job of the operating system is to make best use of the processing type available.

In the space below, draw out the steps of the fetch-execute flowchart

For Next Lesson (Research the purpose of Interrupts in the operating system)



B) Interrupt Handling

What is the purpose of an interrupt?

Name the 5 different types of interrupt service routine (ISR)

No Type Description

1

2

3

4

5

In the space below, draw out the steps of the Interrupt Service Routine. Make sure that you explain the key points and key terms.



C/D) Memory Management

Describe how memory looks in the computer when filled with tasks

Description

Define the following terms:

Disk Thrashing

Virtual Memory

What is the difference between memory and disk storage?

Memory Disk Storage

What is the purpose of memory Management?Mr B Gristwood, 2012 P a g e | 6

My Memory Block


Methods of Memory Management

Describe in the space below the different ways that the operating system manages memory.

Partition MemoryDescription of how it works

Diagram (If needed)

PagingDescription of how it works

Diagram (If needed)

Time SlicingMr B Gristwood, 2012 P a g e | 7


Description of how it works

Diagram (If needed)

SegmentationDescription of how it works

Diagram (If needed)



SpoolingDescription of how it works

Diagram (If needed)

Extension Questions:What would happen if the operating system did not contain memorymanagement features?

Why are there different methods of Memory Management?



F) File Management

Revision: Label the structure of the hard drive.

Boot Files

Boot files are used for when you start the computer, they are a set of commands used to tell the computer what to do. Kind of like a simple computer program that points to the right files. Look at the following Boot file and describe what it is doing:

[boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect



ROM and the Boot File

There is a big difference between ROM and the Boot file. ROM is the hardware check. It is there to establish what each of the parts of the computer hardware is and what it does.

Go into the BIOS in your computer at home (usually by pressing F10 or ESC), havea look at it and detail below what kind of things are in there (Don’t changeanything unless you want a broken computer!)

File Management

File Management is a way of organising all the storage that we have so that it is easier for people to find information.

What ways can you think of to store information so you can find it more easily.

Challenge:

You are the network manager in a school with 800 students and 50 teacher and you have been given a hard drive to partition to make sure there is enough space to store all the data on the network. You have 100gb to organise and have the following sections:

Boot and server files Programs (this is software that is distributed to the rest of the network) User Profiles User Data Print Spooling Files

If any of these becomes overloaded, the server will crash, so you have to be careful of how you allocate your space.

Define: Tree Structure



File Allocation Tables

File allocation Tables are not part of the processor and hardware, but part of the Operating System. They are used to manipulate the Hardware to make it more effective. There are lots of different file allocation tables, e.g. NTFS, FAT, FAT32 but they all have the same principals.

The idea is that data is stored all over the hard drive; the purpose of the FAT is to number each cluster of memory so that data can be accessed quickly.

Write the structure of a File Allocation Table

The Directory Table

Cluster 30030

myfile .doc Hidden, system, archive, directory, R/O, Volume

23/05/1979 30 Kb

What is the difference between the directory table and the file allocation table

Directory Table File Allocation Table(FAT)

Extra task

Find out why we have different File Storage Methods. What is the difference between NTFS, FAT and FAT 32 and what is the point?



End of Unit RecapThe main focus of this unit is how the hardware and the software work together to organise themselves to make the computer the most efficient it can be. There is no use buying the most amazing hard drive, if the Operating System can’t talk to it in a way it understand, this is the battle between hardware and software.

Additional Notes

End of Unit Extension TasksMr B Gristwood, 2012 P a g e | 13





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Introduction - mrgict.files.wordpress.com€¦ · Web viewBy the end of this section you should be able to describe: describe the main features of operating systems – for example,