[COMPUTER SCINCE-REVISION
NOTES]
Michael LAWTHER
,Contents
Structure and function of the processor:................................................................................12
Components of a processor:.............................................................................................................12
Arithmetic Logic Unit:...........................................................................................................................................12
Control Unit:.........................................................................................................................................................12
Registers:..............................................................................................................................................................12
Buses:...................................................................................................................................................................12
Data bus:......................................................................................................................................................12
Address bus:................................................................................................................................................13
Control bus:.................................................................................................................................................13
Assembly language:..............................................................................................................................................13
Pipelining:.........................................................................................................................................13
Fetch-Decode-Execute Cycle:............................................................................................................13
Fetch:....................................................................................................................................................................13
Decode:................................................................................................................................................................14
Execute:................................................................................................................................................................14
Factors affecting CPU performance:..................................................................................................14
Clock Speed:.........................................................................................................................................................14
Number of Cores:.................................................................................................................................................14
Amount and type of Cache Memory:...................................................................................................................14
Computer Architecture:....................................................................................................................14
Von Neumann:.....................................................................................................................................................14
Harvard:................................................................................................................................................................15
Contemporary Processing:...................................................................................................................................15
Types of processor:................................................................................................................16
RISC and CISC processors:.................................................................................................................16
Reduced Instruction Set Computers:...................................................................................................................16
Complex Instruction Set Computers:...................................................................................................................16
Multicore and parallel systems:........................................................................................................16
Graphics Processing Unit:.................................................................................................................16
Input, Output and Storage:....................................................................................................17
Input, output and storage devices:...................................................................................................17
Input devices:.......................................................................................................................................................17
Output devices:....................................................................................................................................................17
Use of storage:..................................................................................................................................17
Optical:.................................................................................................................................................................17
CDs:..................................................................................................................................................................17
DVDs:................................................................................................................................................................18
Blu-Ray:............................................................................................................................................................18
Magnetic:..............................................................................................................................................................18
, Hard Disk Drives:..............................................................................................................................................18
Magnetic Tape:................................................................................................................................................18
Floppy Disks:....................................................................................................................................................18
Flash:....................................................................................................................................................................18
Solid State Drives:............................................................................................................................................19
RAM and ROM:.................................................................................................................................19
Random Access Memory:.....................................................................................................................................19
Read Only Memory:.............................................................................................................................................19
Virtual Storage:.................................................................................................................................19
System software:...................................................................................................................20
Operating Systems:...........................................................................................................................20
Memory Management:.....................................................................................................................20
Paging:..................................................................................................................................................................20
Segmentation:......................................................................................................................................................20
Virtual Memory:...................................................................................................................................................20
Interrupts:........................................................................................................................................21
Interrupt Service Routine:....................................................................................................................................21
Scheduling:.......................................................................................................................................21
Round Robin:........................................................................................................................................................21
First Come First Served:.......................................................................................................................................21
Multilevel Feedback Queues:...............................................................................................................................21
Shortest Job First:.................................................................................................................................................21
Shortest Remaining Time:....................................................................................................................................22
Types of Operating Systems:.............................................................................................................22
Distributed:...........................................................................................................................................................22
Embedded:...........................................................................................................................................................22
Multi-tasking:.......................................................................................................................................................22
Multi-user:............................................................................................................................................................22
Real Time:.............................................................................................................................................................22
Basic Input Output System:..............................................................................................................22
Device Drivers:..................................................................................................................................23
Virtual Machines:.............................................................................................................................23
Intermediate Code:..............................................................................................................................................23
Applications Generation:.......................................................................................................24
Nature of Applications:.....................................................................................................................24
Applications Software:.........................................................................................................................................24
Systems Software:................................................................................................................................................24
Utilities:............................................................................................................................................24
Open-source vs closed source:..........................................................................................................25
Open Source:........................................................................................................................................................25
, Closed Source:......................................................................................................................................................25
Translators:.......................................................................................................................................25
Compiler:..............................................................................................................................................................25
Interpreter:...........................................................................................................................................................26
Assembler:............................................................................................................................................................26
Assembly Code:................................................................................................................................................26
Stages of compilation:......................................................................................................................26
Lexical Analysis:....................................................................................................................................................26
Syntax Analysis:....................................................................................................................................................26
Code Generation:.................................................................................................................................................27
Optimisation:........................................................................................................................................................27
Linkers, Loaders, and use of Libraries:..............................................................................................27
Linkers:.................................................................................................................................................................27
Static:...............................................................................................................................................................27
Dynamic:..........................................................................................................................................................27
Loaders:................................................................................................................................................................27
Use of Libraries:....................................................................................................................................................28
Software Development:.........................................................................................................29
Programming methodologies:..........................................................................................................29
Analysis:................................................................................................................................................................29
Design:..................................................................................................................................................................29
Development:.......................................................................................................................................................29
Testing:.................................................................................................................................................................29
Alpha testing:...................................................................................................................................................30
Beta testing:.....................................................................................................................................................30
White box testing:............................................................................................................................................30
Black box testing:.............................................................................................................................................30
Implementation:...................................................................................................................................................30
Evaluation:............................................................................................................................................................30
Maintenance:.......................................................................................................................................................30
Waterfall cycle:.................................................................................................................................30
Agile methodologies:........................................................................................................................31
Extreme programming:.....................................................................................................................32
Spiral model:....................................................................................................................................32
Rapid Application Development:......................................................................................................33
Writing and following algorithms:....................................................................................................33
Types of Programming Language:.........................................................................................34
Program paradigms:.........................................................................................................................34
Imperative:...........................................................................................................................................................34
Procedural:.......................................................................................................................................................34
Object-oriented:..............................................................................................................................................34
NOTES]
Michael LAWTHER
,Contents
Structure and function of the processor:................................................................................12
Components of a processor:.............................................................................................................12
Arithmetic Logic Unit:...........................................................................................................................................12
Control Unit:.........................................................................................................................................................12
Registers:..............................................................................................................................................................12
Buses:...................................................................................................................................................................12
Data bus:......................................................................................................................................................12
Address bus:................................................................................................................................................13
Control bus:.................................................................................................................................................13
Assembly language:..............................................................................................................................................13
Pipelining:.........................................................................................................................................13
Fetch-Decode-Execute Cycle:............................................................................................................13
Fetch:....................................................................................................................................................................13
Decode:................................................................................................................................................................14
Execute:................................................................................................................................................................14
Factors affecting CPU performance:..................................................................................................14
Clock Speed:.........................................................................................................................................................14
Number of Cores:.................................................................................................................................................14
Amount and type of Cache Memory:...................................................................................................................14
Computer Architecture:....................................................................................................................14
Von Neumann:.....................................................................................................................................................14
Harvard:................................................................................................................................................................15
Contemporary Processing:...................................................................................................................................15
Types of processor:................................................................................................................16
RISC and CISC processors:.................................................................................................................16
Reduced Instruction Set Computers:...................................................................................................................16
Complex Instruction Set Computers:...................................................................................................................16
Multicore and parallel systems:........................................................................................................16
Graphics Processing Unit:.................................................................................................................16
Input, Output and Storage:....................................................................................................17
Input, output and storage devices:...................................................................................................17
Input devices:.......................................................................................................................................................17
Output devices:....................................................................................................................................................17
Use of storage:..................................................................................................................................17
Optical:.................................................................................................................................................................17
CDs:..................................................................................................................................................................17
DVDs:................................................................................................................................................................18
Blu-Ray:............................................................................................................................................................18
Magnetic:..............................................................................................................................................................18
, Hard Disk Drives:..............................................................................................................................................18
Magnetic Tape:................................................................................................................................................18
Floppy Disks:....................................................................................................................................................18
Flash:....................................................................................................................................................................18
Solid State Drives:............................................................................................................................................19
RAM and ROM:.................................................................................................................................19
Random Access Memory:.....................................................................................................................................19
Read Only Memory:.............................................................................................................................................19
Virtual Storage:.................................................................................................................................19
System software:...................................................................................................................20
Operating Systems:...........................................................................................................................20
Memory Management:.....................................................................................................................20
Paging:..................................................................................................................................................................20
Segmentation:......................................................................................................................................................20
Virtual Memory:...................................................................................................................................................20
Interrupts:........................................................................................................................................21
Interrupt Service Routine:....................................................................................................................................21
Scheduling:.......................................................................................................................................21
Round Robin:........................................................................................................................................................21
First Come First Served:.......................................................................................................................................21
Multilevel Feedback Queues:...............................................................................................................................21
Shortest Job First:.................................................................................................................................................21
Shortest Remaining Time:....................................................................................................................................22
Types of Operating Systems:.............................................................................................................22
Distributed:...........................................................................................................................................................22
Embedded:...........................................................................................................................................................22
Multi-tasking:.......................................................................................................................................................22
Multi-user:............................................................................................................................................................22
Real Time:.............................................................................................................................................................22
Basic Input Output System:..............................................................................................................22
Device Drivers:..................................................................................................................................23
Virtual Machines:.............................................................................................................................23
Intermediate Code:..............................................................................................................................................23
Applications Generation:.......................................................................................................24
Nature of Applications:.....................................................................................................................24
Applications Software:.........................................................................................................................................24
Systems Software:................................................................................................................................................24
Utilities:............................................................................................................................................24
Open-source vs closed source:..........................................................................................................25
Open Source:........................................................................................................................................................25
, Closed Source:......................................................................................................................................................25
Translators:.......................................................................................................................................25
Compiler:..............................................................................................................................................................25
Interpreter:...........................................................................................................................................................26
Assembler:............................................................................................................................................................26
Assembly Code:................................................................................................................................................26
Stages of compilation:......................................................................................................................26
Lexical Analysis:....................................................................................................................................................26
Syntax Analysis:....................................................................................................................................................26
Code Generation:.................................................................................................................................................27
Optimisation:........................................................................................................................................................27
Linkers, Loaders, and use of Libraries:..............................................................................................27
Linkers:.................................................................................................................................................................27
Static:...............................................................................................................................................................27
Dynamic:..........................................................................................................................................................27
Loaders:................................................................................................................................................................27
Use of Libraries:....................................................................................................................................................28
Software Development:.........................................................................................................29
Programming methodologies:..........................................................................................................29
Analysis:................................................................................................................................................................29
Design:..................................................................................................................................................................29
Development:.......................................................................................................................................................29
Testing:.................................................................................................................................................................29
Alpha testing:...................................................................................................................................................30
Beta testing:.....................................................................................................................................................30
White box testing:............................................................................................................................................30
Black box testing:.............................................................................................................................................30
Implementation:...................................................................................................................................................30
Evaluation:............................................................................................................................................................30
Maintenance:.......................................................................................................................................................30
Waterfall cycle:.................................................................................................................................30
Agile methodologies:........................................................................................................................31
Extreme programming:.....................................................................................................................32
Spiral model:....................................................................................................................................32
Rapid Application Development:......................................................................................................33
Writing and following algorithms:....................................................................................................33
Types of Programming Language:.........................................................................................34
Program paradigms:.........................................................................................................................34
Imperative:...........................................................................................................................................................34
Procedural:.......................................................................................................................................................34
Object-oriented:..............................................................................................................................................34
