Edexcel Gcse Computing - Computers And Assembly Language

Front 1

CPU

Back 1

Central Processing Unit

Front 2

Central Processing Unit

Back 2

Fetches, decodes and executes instructions, controls the movement of data between components, controls the operations of the computer, performs logical and arithmetical operations on the data. Processes data.

Front 3

Register

Back 3

A component in the CPU that provides a small amount of temporary storage for instructions, data or memory addresses.

Front 4

Address bus

Back 4

Carries the address of a location in primary memory or I/O device. It is unidirectional as it only carries the address from the CPU to memory or the device.

Front 5

How address bus width determines maximum memory available

Back 5

Each line/wire in the address bus can carry 1 bit of data. The number of the address bus can carry (or the number of wires/lines it has), determines how many unique memory locations may be addressed and used. i.e. the more lines/wires/bits, the more memory may be addressed.

Front 6

Calculating maximum addressable memory

Back 6

The formula to calculate the maximum addressable memory based on address bus size is 2^n, where 'n' is the size of the address bus in bits. For example, a 32 bit address bus can address 2^32 = 4294967296 unique memory locations.

Front 7

Memory

Back 7

This refers to primary (or main) memory. It is memory that is directly accessible by the CPU. It is often used to refer to RAM.

Front 8

RAM

Back 8

Random Access Memory

Front 9

Random Access Memory

Back 9

Temporarily stores the instructions, data and addresses currently being used being used by the CPU -OR- temporarily stores the instructions, data and addresses of running programs. RAM is volatile, meaning its contents are only stored as long as the computer has power. RAM is used to store currently running programs because it is faster than secondary storage.

Front 10

Bit

Back 10

The smallest unit of data in a computer system, represented but a 1 or 0.

Front 11

Bus

Back 11

A component of a computer system that transfers instructions, data and signals between the components of the computer.

Front 12

Clock speed

Back 12

The speed of the processor (CPU) in cycles per second, measured in hertz (Hz). 1 million cycles per second = 1 megahertz (MHz). 1 billion cycles per second = 1 gigahertz (GHz).

Front 13

Digital Computer

Back 13

Automatic, programmable data processor

Front 14

*Digital*, programmable, automatic computer

Back 14

The computer only understands the binary quantities that take two values, 1 or 0.

Front 15

Digital, *programmable*, automatic computer

Back 15

The computer can execute instructions stored as a program

Front 16

Digital, programmable, *automatic* computer

Back 16

The computer can operate without human intervention, except where human intervention is planned.

Front 17

ALU

Back 17

An arithmetic-logic unit (ALU) is the part of a computer processor (CPU) that carries out arithmetic and logic operations on the operands in computer instruction words. In some processors, the ALU is divided into two units, an arithmetic unit (AU) and a logic unit (LU).

Front 18

Program

Back 18

a sequence of instructions, stored in any medium, that can be interpreted and executed by a computer

Front 19

Accumulator

Back 19

An accumulator is a register for short-term, intermediate storage of arithmetic and logic data in a computer's CPU (central processing unit).

Front 20

data bus

Back 20

The width and clock rate of the data bus determine its data rate (the number of bytes per second it can carry), which is one of the main factors determining the processing power of a computer. Most current processor designs use a 32-bit bus, meaning that 32 bits of data can be transferred at once.

Front 21

Secondary Storage

Back 21

Non-volatile storage not under direct control of the CPU. May be used by the CPU if main memory becomes full. Secondary storage is much slower than primary memory.

Front 22

Multi-core

Back 22

A multi-core processor is a single computing component with two or more independent actual processing units (called "cores"), which are the units that read and execute program instructions.

Front 23

Process

Back 23

In computing, a process is an instance of a computer program that is being executed

Front 24

Operating System

Back 24

An operating system (OS) is software that manages computer hardware and software resources and provides common services for computer programs. The operating system is an essential component of the system software in a computer system. Application programs usually require an operating system to function

Front 25

Input Device

Back 25

A device in which submits an instruction or action to the CPU, usually controlled by the user.

Front 26

Instruction Register

Back 26

In computing, an instruction register (IR) is the part of a CPU's control unit that stores the instruction currently being executed or decoded.

Front 27

Volatile

Back 27

Memory that is only intact when it is powered on. All data is lost when power to the memory is lost.

Front 28

Non-Volatile

Back 28

Memory that is saved when the power is turned off. No data is lost when the system power is turned off.

Front 29

Silicon

Back 29

Silicon is the basic material used to make computer chips, transistors, silicon diodes and other electronic circuits and switching devices

Front 30

Transistor

Back 30

A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit.

Front 31

optical storage

Back 31

Optical Storage is data that can be read through the use of light, usually a beam of light is used on a spinning disc

Front 32

Memory Addressing

Back 32

A number that is assigned to each byte in a computer's memory that the CPU uses to track where data and instructions are stored in RAM. Each byte is assigned a memory address whether or not it is being used to store data. The computer's CPU uses the address bus to communicate which memory address it wants to access, and the memory controller reads the address and then puts the data stored in that memory address back onto the address bus for the CPU to use.

Front 33

Graphics card

Back 33

Processor dedicated to rendering geometry (3d, 2d) such as polygons.

Front 34

ASCII

Back 34

A common format to show alphabetic, numeric, or special characters in a 7-bit binary number.

Front 35

GUI

Back 35

Graphical User Interface - a visual interface enabling interaction with a computer system using graphical elements such as icons, buttons and menus.

Front 36

Computer Network

Back 36

A group of computers and other electronic devices connected together with the ability to share data with each other.

Front 37

Gigabyte

Back 37

A gigabyte (GB) is a measure of computer data storage capacity that is roughly equivalent to 1 billion bytes.

Front 38

Embedded computer

Back 38

An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints

Front 39

Computer Network

Back 39

A computer network or data network is a telecommunications network which allows computers to exchange data. In computer networks, networked computing devices pass data to each other along network links (data connections). Data is transferred in the form of packets.

Front 40

machine code

Back 40

A set of instructions consisting of binary or hexadecimal codes which may be executaed directly by the CPU

Front 41

5 Examples of a Input Device

Back 41

mouse, keyboard, microphone, joystick, graphics tablet, webcam, digital camara, digital camcorder, image scanner, fingerprint scanner, barcode reader, 3D scanner, laser rangefinder, interactive whiteboard

Front 42

Hard Disk

Back 42

A rigid non-removable magnetic disk with a large data storage capacity

Front 43

Operand

Back 43

A value provided as part of an assembly language instruction. An operand refers to an address location of data or a peripheral device on which the instructions operates.

Front 44

Name 5 types of processor

Back 44

ARM, AMD, INTEL, Texas instruments, Snapdragon

Front 45

Graphical User Interface

Back 45

Graphical User Interface - a visual interface enabling interaction with a computer system using graphical elements such as icons, buttons and menus.

Front 46

Opcode

Back 46

A specific instruction in assembly language represented by a mnemonic such as ADD, MOV, or LDR.

Front 47

Kilobyte

Back 47

A unit of storage or information equal to 1,024 bytes.

Front 48

Megabyte

Back 48

A unit of storage or information equal to 1,048,576 bytes OR 1,024 * 1,024 bytes OR 1,024^2 bytes

Front 49

Gigabyte

Back 49

A unit of storage or information equal to 1,073,741,824 bytes OR 1,024 * 1,024 * 1,024 bytes OR 1,024^3 bytes

Front 50

Terabyte

Back 50

A unit of storage or information equal to 1,099,511,627,776 bytes OR 1,024 * 1,024 * 1,024 * 1,024 bytes OR 1,024^4 bytes

Front 51

Control bus

Back 51

The control bus is used by the CPU to control other devices. It carries commands from the CPU to devices, and status signals back from devices to the CPU.

Front 52

control unit

Back 52

The control unit controls the flow of instructions and data in the CPU - the Fetch-Decode-Execute cycle. It controls and organises the input and output of data and the hardware attached to the computer, ensuring it responds to instructions correctly.

Front 53

Embedded computer

Back 53

An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system. It usually consists of a single chip with all the components necessary to make a complete computer system - i.e. RAM, ROM, CPU, input, output, clock.

Front 54

5 examples of output devices

Back 54

Examples of output devices are: speakers, projectors, monitors, printers (e.g. 3d, dot matrix, inkjet, laser), laser cutter, braille embosser

Front 55

Fetch-*Decode*-Execute cycle

Back 55

(1) Decode the instruction. (2) If the instruction uses data from memory, identify the memory addresses and fetch the data from memory.

Front 56

Fetch-Decode-*Execute* cycle

Back 56

(1) Execute the instruction.(2) Store results in a register.

Front 57

*Fetch*-Decode-Execute cycle

Back 57

(1) Fetch the next instruction from main memory using the memory address in the program counterregister. (2) Increment the program counter to point to the next instruction.

Front 58

Fetch-Decode-Execute cycle

Back 58

Describes the most basic operation of the computer. The CPU fetches an instruction from memory as machine code,decodes the instruction, and then executes it.

Front 59

Compiler

Back 59

A compiler is a program that takes a program written in a high level language such a Python or C and translates it into assembly language or machine code that a particular processor can understand and run.

Front 60

computer architecture

Back 60

Refers to all hardware components that make up a cmoputer system. The choice of hardware components affects the computer’s speed and power, as well as how much the computer costs and how it can be used.

Front 61

Command Line Interface

Back 61

A type of user interface. The user interacts with the computer by typing in commands (instructions) at a prompt and pressing enter to instruct the computer to execute them. An example is DOS (Disk Operating System).

Front 62

Application Software

Back 62

Application software is a set of computer programs which allows the user to perform a specific task or group of tasks. Application software cannot run by itself and needs system software to execute. Examples include: word processors, spreadsheets, image editing software, video editing software, 3D modelling software (IMPORTANT: in an exam, provide general examples like this. Do not provide specific examples such as Excel, Photoshop, Flash).

Front 63

Arithmetic and Logic Unit

Back 63

The ALU is the part of a processor (CPU) that is used to carry out arithmetic and logic operations, using operands (the data to be operated on) and a code which indicates the operation to be performed.

Front 64

ARM Processor

Back 64

An ARM Processor is a family of CPUs based on the RISC architecture. ARM Processors are used in portable devices such as smartphones as they have low power usage compared to other CPUs. Also, because of their reduced instruction set fewer transistors are required which decreases the overall size of the CPU die.

Front 65

Executable

Back 65

A file containing instructions that may be run as a program on a computer. An executable is created when a compiler converts high level programming code into a low level language.

Front 66

Storage Device

Back 66

A piece of hardware capable of permanently storing programs or data. Examples include harddisk drives, SDcards and solid state memory.

Front 67

input- process-output model

Back 67

The general model on which all modern computers function. The computer receives input, process the data or information, and produces and ouput.

Front 68

FIFO

Back 68

An acronym for First In, First Out, a method for organising a queue of instructions in which instructions are educated in the order in which they joined the queue - i.e. oldest first.

Front 69

Key function of an operating system: Network management

Back 69

The operating system manages the operation of the computer system’s network connections

Front 70

Key function of an operating system: Input / output management

Back 70

The operating system manages data transfers between the CPU and the input and output devices, such as the keyboard and printers. The software that allows this data transfer may already be part of the operating system, or the user might need to install a driver to handle input and output from a particular device.

Front 71

Key function of an operating system: Process management

Back 71

The operating system assigns each process a unique ID; allocates space in memory to hold the instructions and data for a program; assignspriority which determines the order in which processes will run; links processes with a specific user.

Front 72

instruction register

Back 72

In computing, an instruction register (IR) is the part of a CPU's control unit that stores the instruction currently being executed or decoded.

Front 73

instruction set

Back 73

A set of instructions that are understood by a specific family of processors. The instruction set forms the low level programming language used by that computer.

Front 74

Key function of an operating system: File management

Back 74

The operating system manages the storage of files and directories (folders), allocating space for these in secondary storage.

Front 75

Parallel Processing

Back 75

In computers, parallel processing is the processing of program instructions by dividing them among multiple processors with the objective of running a program in less time. In the earliest computers, only one program ran at a time.

Front 76

6 key functions of an operating system

Back 76

(1) File management; (2) Input/output management; (3) Resource allocation; (4) Process management; (5) Network management; (6) User management

Front 77

Algorithm

Back 77

In computer science, a set of instructions to be carried out by a computer in a specific order to solve a problem or accomplish a task.