Computer Systems. IGCSE OCR AQA Edexcel Understand the term. embedded system and how an Purpose of embedded system

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1 This scheme gives pupils an introduction to computer systems and begins with students getting a real idea of the functions of the main hardware components by creating their own cardboard laptop. By looking at various examples, students learn to recognise different types of computer system and understand a simple input-process-storage-output model. Students then move on to identifying and describing input devices and automatic sensors as they learn about how computers find out about their environment. Python programming is introduced so that students are able write suitable statements to ask users for information and understand what assignment involves. Next, students investigate the difference between data and information and begin to look at data types and how computers store data on an electrical level. In a fun and practical lesson, with a focus on literacy and collective nouns, students learn the terminology used in engineering and computing to quantify data before finally looking a number bases and learning how to convert from one number base to another. This scheme ends with an assessment checking students understanding of the topics covered and their ability to demonstrate their understanding of why binary is so important to Computer Scientists. Lesson 1 Introduction to Computer Systems "What is a computer system, really?" The 'big picture' of computer systems including an overview of all the major components with a special focus on embedded systems. Suitable for all examination boards but not explicitly covered in igcse. Lesson 2 HCI Input "How do computers find out about their environment?" A detailed look at various input IGCSE OCR AQA Edexcel Understand the term Embedded systems embedded system and how an Purpose of embedded system embedded system differs from Examples of embedded a non-embedded system. systems Input devices Describe the principles of operation (how each device works) of these input devices: 2D and 3D scanners, barcode readers, Quick Response (QR) code readers, Understand the inputprocess-output model Understand the function of the hardware components of a computer system (CPU, main memory, secondary storage) and how they work together Understand the need for embedded systems and their functions

2 devices in use in common computer systems. Only covered in the igcse specification but a quick overview would be useful for all examination boards. The lesson also serves as an introduction to programming environments using simple input routines. Lesson 3 Dealing with input "What practical methods can I use to tell the computer things?" digital cameras, keyboards, mice, touch screens, interactive whiteboard, microphones Describe how these principles are applied to reallife scenarios, for example, scanning of passports at airports, barcode readers at supermarket checkouts, and touch screens on mobile devices Describe how a range of sensors can be used to input data into a computer system, including light, temperature, magnetic field, gas, pressure, moisture, humidity, ph and motion. Describe how these sensors are used in real-life scenarios, for example; street lights, security devices, pollution control, games and household and industry applications. Understand and use the pseudocode for assignment using <- Be able to obtain use input from the keyboard Understand how to write code that accepts and responds appropriately to user input.

3 A practical lesson introducing the Python programming environment focusing on the distinction between the programmer and the user, and writing suitable prompts to get user input. Dealing with Input is Not explicitly stated in the AQA specification but it should still be covered as the skills will be required later in the course. Lesson 4 Naming data "There are loads of different types of data - how can it be classified?" A detailed study look of the many ways in which data is classified. It introduces the concept of the data type and the need to name data in order to identify it. It is suitable for all examination boards. Understand and use basic data types; Integer, Real, Char, String and Boolean Programming concepts Declare and use variables and constants Recognise the use of binary numbers in computer systems Show understanding that sound (music), pictures, video, text and numbers are stored in different formats Understand and use the following appropriately: Integer Real Boolean Character String Understand that computers use binary to represent all data and instructions Understand the concept of a data type Use meaningful identifier names and know why it is important to use them. The use of data types; Integer Real Boolean Character and String Why data is represented in computer systems in binary form How data needs to be converted into binary form to be processed by a computer Understand the need for, and understand how to use, data types (integer, real, Boolean, char) Understand the need for, and how to use, variables and constants Understand that computers use binary to represent data (numbers, text, sound, graphics) and program instructions Lesson 5 Quantifying data Show understanding of the concept of a byte and how the byte is used to measure Know that: a bit is the fundamental unit of information Bit, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte Understand how to convert between the terms bit, nibble, byte, kilobyte (KB),

4 "How is data 'measured'?" A detailed look at the collective ways in which computer scientists can group data. It is required by all examination boards. Lesson 6 Number Bases "We understand numbers from 1 to 10 because we've got 10 fingers, but computers haven't got hands!" How denary numbers are represented in computer systems. Introduction to Hexadecimal as an abbreviation of binary. It is required by all examination boards. memory size. Convert positive denary integers into binary and positive binary integers into denary (a maximum of 16 bits will be used) Hexadecimal Represent positive numbers in hexadecimal notation Show understanding of the reasons for choosing hexadecimal notation to represent numbers Convert positive hexadecimal integers to and from denary (a maximum of four hexadecimal digits will be required) Convert positive hexadecimal integers to and A byte is a group of 8 bits Know that quantities of bytes can be described using prefixes. Know the names, symbols and corresponding values for decimal prefixes: Kilo, 1kB is 1,000 bytes Mega, 1 MB is 1,000 kilobytes Giga, 1 GB is 1,000 megabytes Tera, 1 TB is 1,000 gigabytes Understand how binary can be used to represent whole numbers Understand how hexadecimal can be used to represent whole numbers Explain why hexadecimal is often used in computer science How to convert positive denary whole numbers (0-255) into 8 but binary numbers and vice versa How to convert positive denary whole numbers (0-255) into 2 digit hexadecimal numbers and vice versa How to convert from binary to hexadecimal equivalents and vice versa megabyte (MB), gigabyte (GB), terabyte (TB) Understand that file storage is measured in bytes and be able to calculate file sizes to be able to convert between binary and denary whole numbers (0-255) understand why hexadecimal notation is used and be able to convert between hexadecimal and binary

5 from binary (a maximum of 16 bit binary numbers will be required) Represent numbers stored in registers and main memory as hexadecimal Identify current uses of hexadecimal numbers in computer, such as defining colours in Hypertext Markup Language (HTML), Media Access Control (MAC) addresses, assembly language and machine code, debugging Use binary in computer registers for a given application (such as in robotics, digital instruments and counting systems) Assessment Reflection question Effort Grading [10] How is data retrieved and stored by computers? Why is binary so important to computer scientists? Examination Style Questions [20]