OCR H446/01 – 1.2 Software and software development

Posted on by Administrator Posted in H446 - Computer Science A Level (OCR)
1.2 Software and software development - Overview / Checklist
1.2.1 Systems Software
(a) The need for, function and purpose of operating systems.
(b) Memory Management (paging, segmentation and virtual memory).
(c) Interrupts, the role of interrupts and Interrupt Service Routines (ISR), role within the Fetch-Decode-Execute Cycle.
(d) Scheduling: round robin, first come first served, multi-level feedback queues, shortest job first and shortest remaining time.
(e) Distributed, embedded, multi-tasking, multi-user and Real Time operating systems.
(f) BIOS.
(g) Device drivers.
(h) Virtual machines, any instance where software is used to take on the function of a machine, including executing intermediate code or running an operating system within another.
1.2.2 Applications Generation
(a) The nature of applications, justifying suitable applications for a specific purpose.
(b) Utilities.
(c) Open source vs closed source.
(d) Translators: Interpreters, compilers and assemblers.
(e) Stages of compilation (lexical analysis, syntax analysis, code generation and optimisation).
(f) Linkers and loaders and use of libraries.
1.2.3 Software Development
(a) Understand the waterfall lifecycle, agile methodologies, extreme programming, the spiral model and rapid application development.
(b) The relative merits and drawbacks of different methodologies and when they might be used.
(c) Writing and following algorithms.
1.2.4 Types of Programming Language
(a) Need for and characteristics of a variety of programming paradigms.
(b) Procedural languages.
(c) Assembly language (including following and writing simple programs with the Little Man Computer instruction set).
(d) Modes of addressing memory (immediate, direct, indirect and indexed).
(e) Object-oriented languages with an understanding of classes, objects, methods, attributes, inheritance, encapsulation and polymorphism.

Recommended Resources

1.2.1 Systems Software

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1.2.2 Applications Generation

The 4 Stages of the Compilation Process

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1.2.3 Software Development
Python Challenges
1.2.4 Types of Programming Language

Assembly Language

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Object-Oriented Programming Concepts

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LMC Simulator LMC Mini Challenges LMC Burglar Alarm LMC 5-4-3-2-1 LMC Max Function LMC Countdown Timer LMC Higher or Lower Game LMC Finding the factors of… LMC Step Count Algorithm LMC Fibonacci Sequence LMC Triangular Numbers LMC Trace Table LMC Multiplication LMC Factorial

Procedural Programming
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Solving a Murder Mystery Using Prolog Sorting Hat Challenge (Prolog) Family Tree Challenge (Prolog) Food Web Challenge (Prolog)

OOP Challenges
OOP Quiz! OOP Terminology OOP Crossword Inheritance Q&A Encapsulation Q&A Classes & Objects Multimedia Library (OOP) My MP3 Playlist (OOP) Shopping Basket Class

Further Reading…

Extra Resources
UML Diagrams Solving a Zebra Puzzle using Prolog
Bubble Sort Algorithm in LMC Memory Filler in LMC Self-Modifying Code in LMC Stacks and Queues in LMC

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