Karteikarten
Computer Systems
Karten in diesem Stapel (149)
- 1in computing what can a binary 1 and 0 represent?a 1 = true and 0 = false
- 2name the four Boolean operatorsAND, OR, NOT and XOR
- 3what does a truth table represent?A truth table shows the output from all possible combinations of inputs from a Boolean expression
- 4what is the truth table that represents the boolean function of AND(Copy this in)
- 5what is the truth table that represents the boolean function of OR?(Copy this in)
- 6what is the truth table that represents the boolean function of NOT?(copy this in)
- 7what is the truth table that represents the boolean function of XOR?(copy this in)
- 8what is the logic statement for AND (with symbol)A.B
this means A AND B - 9what is the logic statement for OR (with symbol)(y =) A+B
this means A OR B - 10what is the logic statement for NOT (with symbol)(Y =) (copy this in)
This means NOT A - 11what is the logic statement for XOR (with symbol)(Y=) A B
this means A XOR B
(copy this in) - 12What is the logic for AND?Both inputs must be true for the output to be true
- 13What is the logic for OR?Only one input must be true for the output to be true
- 14What is the logic for XOR?If JUST one input is 1 (true) then the output is 1 (true)
Otherwise, the output is 0 (false) - 15What is the logic for NOT?If the input is true, the output will be false and vice versa
- 16what is the gate for AND?copy pic in
- 17what is the gate for OR?copy pic in
- 18what is the gate for XOR?copy pic in
- 19what is the gate for XOR?copy pic in
- 20what is the logic statement for this combined logic table (insert table one here)P =(not line) A.B
- 21what is the logic statement for this combined logic table? insert table two here(S.N) + B
- 22draw the boolean expression for: P = (not line)A.(B.C)insert drawing here
- 23(Start of application and software) what is hardware?it's the physical components that make up a computer system
- 24what does hardware include?This includes input/output/ storage devices CPU and RAM
- 25what are some examples for input devices?keyboard, mouse, trackpad, games controller, remote control, microphone, webcam, graphics tablet
- 26what are some examples for output devices?display screen, printer, speakers
- 27what are some examples of storage devices?hard drive, CD / DVD / Blu-ray drive, SD cards and flash media
- 28what is software?Software is the non-physical programs that are stored by and run on a computer system
- 29what does software do?Software makes use of physical hardware components and devices as the way of:
Taking inputs from users
Outputting information to users
Storing information - 30what are some examples of software?operating system, computer games, web browser, email client, photo editing software
- 31what is an operating system?An operating system is a special type of computer software
- 32what are 3 examples of operating systems?Microsoft: MS-DOS (1981-2000, Windows (1985-present)
Google: Android (2008 – present), Chrome OS (2011-present)
Apple : MacOS (2001-present), IOS - 33what do operating systems do and what are they responsible for?Operating systems (OS) manage computer hardware, users and the resources used by software
they are responsible for: Processor(s), Memory, Input/output devices, ApplicationsSecurity - 34what are the two types of software?system software and application software
- 35what are the two types of system software it includes?Utility programs and operating systems
- 36what is system software?System software is the software that provides a platform for other software to work
- 37what are programs run by?Programs are run by one or more processors
- 38true or false: one processor can only have one core.False:
A single processor can have a number of cores - 39what is the operating system responsible for in terms of programs?The operating system is responsible for deciding with program will run on the processor (CPU) and how much time it will get to run
- 40what is multi-tasking in terms of an operating system and give an exampleMulti-tasking is where an operating system manages many tasks happening at the same time. This may be having a web browser open whilst playing music and messaging friends. Many other background processes are also running
- 41what are interrupts?Interrupts are signals sent to the CPU by external devices to indicate an event that needs immediate attention.
- 42what do interrupts do?They tell the CPU to suspend its current activities and execute appropriate instructions
- 43what are hardware interrupts?they interrupts that are generated by hardware devices – for example printer out of paper
- 44what are software interrupts?they are interrupts that are generated by programs for example a divide by zero error will cause an error message to be displayed
- 45to run a program what has to happen?To run a program the computer must copy the program from storage into the main memory.
- 46when a program is run what happens?Data used by the program is copied into main memory. The operating system keeps a record of where each program and its data are located. The operating system will make sure not to overwrite existing programs and data
- 47true or false: The operating system must manage input/output devicesTrue
- 48when an operating system manages input/output devices, what does that include?Getting inputs from and sending outputs to peripheral devices
- 49what are some examples of peripheral devices?mice, keyboard, printers, displays, digital cameras and graphics tablets
- 50What item of software needs to be installed for each peripheral to work?Device drivers
- 51what's a device driver?A device driver is a program that controls peripheral devices such as printers, mice and displays, each device communicates with the OS via its own driver
- 52what happens when you send a data to a printer?The computer can send data to a printer much faster than it can be printed. The data will be sent to a print queue or buffer which is a special area of memory in a computer print server or the printer itself
- 53what happens to the data sent to a printer when it's in the print queue?Any data in the print queue is transmitted to the printer, typically a page at a time The printer will send its status back to the operating system which reports any errors to the user. For example, the operating system may display an 'out of paper' error message
- 54what do applications include?applications include office software including word processors and spreadsheets
- 55what are some types of application software?Web browsers, music and video players, PDF viewers, email clients and instant messaging software
- 56operating system application management: what does the operating system (OS) provide that can be shortened to GUI features?The operating system (OS) provides graphical user interface (GUI) features such as windows, minimise, maximise, resize.
- 57what does the operation system (OS) do when an application is opened?When an application is opened the OS will copy the program into RAM and allocate an area of RAM for the program to use
- 58what does the operation system (OS) do when an application is closed?When an application is closed the operating system will make sure that it is removed from the RAM
- 59what may also be responsible for installing and updating programs?The operating system may also be responsible for installing and updating programs
- 60security management: what is the operating system responsible for keeping secure?The computer system and operating system,
Application programs,
User data - 61what does the security in the operating system do?it reduces risks from hackers and other users
- 62what are the security features that operating systems often contain?User management with usernames and passwords, Memory protection prevention of programs being able to view or overwrite other programs data stored in RAM, Encryption of hard drives and removable media, Access rights to files, programs and services, Security updates are automatically downloaded and installed
- 63what do access do and what are they used for?If a computer is used by more than one person, each user should be able to see only their own files, Users and system administrators have different levels of access rights, some users may be allowed to read files but not edit them
- 64what do operating system come bundled with to keep them working well?these are utility softwares
- 65what are the utility softwares?Encryption software, Defragmentation software, Data compression, Disk clean-up tools, Disk formatters, Anti-virus software
- 66what does a utulity software do?Utility programs perform extra functionality and housekeeping tasks that keep computers running efficiently, they are often packages as part of the operating system, Some utility programs, such as anti-virus software, are bought as stand-alone software programs
- 67what does the operating system do simply?The operating system controls and manages the computer system
- 68what is encryption software used to do?Encryption software is used to encode text so that it cannot be understood without knowing the key to decode it
- 69how do you know if a websites connection of encrypted?Web browsers usually show a padlock for sites that are using HTTPS (Hypertext Transfer Protocol Secure)
- 70what organisations would encrypt file attachments or emails? Why?Councils when discussing sensitive personal information such as special needs or disabilities, Accountants discussing financial information of companies, Companies sharing confidential internal files
- 71encryption tools: what are encryption software utilities commonly used for?Encrypt entire hard disks so that the data cannot be understood if computer is stolen, encrypt files and folders on a portable disk such as a USB removable storage, encrypt communications with websites, encrypt data is any organization's database – especially sensitive information such as passwords
- 72why would a file be referred to as fragmented?When you save a large file, it may not fit on the disk in conservative memory locations. The file is referred to as 'fragmented'
- 73what will happen when you read a file that is fragmented?To read the file, the drive head will need to move to more locations. This makes it far slower to access files and programs
- 74what does disk defragmentation mean?Defragmenting the hard drive reorganizes files so that they are stored together, read times are far faster, Free space is also in one place, so new files do not need to be fragmented
- 75what does data compression software do?This reduces the amount of storage space needed on a disk If sending files, it reduces the amount of data that is sent, Compression may allow attachments to be sent via email that would otherwise have been larger than a file-size limit. More data can be stored on backup media
- 76what is an embedded computer, and what are they used to do?An embedded computer is a single microprocessor that includes RAM, ROM, and a CPU, it is frequently used to control a device using simple inputs
- 77what utilities allow users to compress and decompress files or folders?WinZip
- 78what is an embedded system?An embedded system is a computer system —a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system.
- 79what does a embedded system allow digital devices to do?to perform specific functions
- 80what are examples of embedded systems?in cars this could be cruise control, engine cooling fan, interior lighting
a satnav, a washing machine to heat water. - 81what are some examples of non-embedded systemsNon embedded systems include desktop computers, laptops, tablets, and smartphones
- 82how do embedded systems differ from non-embedded systems with: CPU speedEmbedded system; Typically slow
non - embedded system typically very fast - 83how do embedded systems differ from non-embedded systems with: softwareembedded system:
Has one purpose and cannot install new software
non-embedded system:
New software can be installed - 84how do embedded systems differ from non-embedded systems with: storageembedded system: Programs stored om ROM
non-embedded system: Programs stored on hard drives - 85how do embedded systems differ from non-embedded systems with: Reliabilityembedded systems:
Typically, very reliable, e..g. a microwave should not have a bug that changes defrost to full power
non-embedded systems:
As it runs many software programs it may be less reliable and need restarting the device - 86where was machine code used?in the first computers made instructions were in machine code
- 87what were the instructions in machine code written in?binary.
- 88what were some of the problems with machine code?Writing programs was difficult and time-consuming
- 89what is assembly code?Assembly language allows a programmer to create programs more easily than writing in machine code
Each instruction in assembly language maps directly to machine code - 90true or false: processors can still only execute instructions in machine codetrue
- 91what is machine code instructions specific to?The machine code instructions will be specific to a particular processor or family of processors
- 92true or false: assembly code is like machine and is processor specifictrue
- 93what does assembly code have to have done for it to be able to be executedPrograms written in assembly language must be translated to machine code in order to be run ?
- 94what does the program known as the assembler do? (To do with machine and assembly code)the program known as the assembler translates assembly code into machine code, so it is able to be executed.
- 95what are machine and assembly code classed as?low level languages.
- 96what is the ratio of correspondence between assembly code and machine code of it being translated?There is a 1:1 correspondence between assembly language and machine code
- 97when is assembly code still used today?assembly language is typically only used for following types of software:
Software used in embedded systems, such as a washing machine or microwave. The software used to control specific hardware components such as device drivers - 98what does assembly code allow programmers to do?Assembly language allows the programmer to precisely control any instruction on the processor. This means that programs can be made to be very efficient. For, instance when a graphics device driver is programmed to run quickly and make use of all the advancement
- 99which is harder to learn: low level languages or high-level languageshigh level languages
- 100why are high level languages easier to understand and learn?this is because High-level languages generally have statements that look a bit like English or Maths:
Area = (base*height)/2, Print(area).
This makes these languages easier to understand and learn - 101what data structures do high level languages have ?arrays and records
- 102what have many high-level languages been especially designed to do?Many high-level languages have been especially designed to make it as easy as possible to write programs to solve certain types of problem
- 103true or false: These languages must be translated into machine code in order to run and a single statement usually translates into multiple machine code instructions true
- 104the translations of high-level languages into machine code is usually down by which two types of programsa complier or an interpreter
- 105what are the advantages of using a high-level language?A high-level language is easier to learn
Programs can be written faster in a high-level language
It is easier to understand and debug a high-level language - 106Why do you think low-level languages are still used by some programs?As a programmer had direct control over how a low-level program works, they have a number of advantages: A program written is a low-level language can run very quickly. The code will usually require less RAM. Statements in a low-level language can be used to control and manipulate specific hardware components
- 107what does a complier do?A complier translates ahigh-level language in machine code. The machine code produced can be saved on a storage device and run whenever required
- 108what do you call the code written by a programmer?the source code
- 109what is an interpreter and how does it differ from a complier?An interpreter is another type of program that translates a high-level language into machine code. Unlike a complier, no object code is produced. It translates each line of code and executes it immediately. If it reaches a line with a syntax error, it stops and displays an error message
- 110how does an interpreter, complier and assembler compare on: input?interpreter:
Complier:
Assembler: - 111how does an interpreter, complier and assembler compare on: input?interpreter: A high-level language
Complier: A high-level language
Assembler: Assembly language - 112how does an interpreter, complier and assembler compare on: output?interpreter: No output – program runs straight away
Complier: Machine code
Assembler: Machine code - 113how does an interpreter, complier and assembler compare on: how it works?interpreter: Translates source code and immediately run it
Complier: Compile source code so it can be run later
Assembler: Assemble source code so it can be run later - 114how does an interpreter, complier and assembler compare on: speed of execution?interpreter: Slow as needs to be translated each time it is run
Complier: Fast as it just runs the machine code
Assembler: Fast as it just runs the machine code - 115how does an interpreter, complier and assembler compare on: What end users need to run program?interpreter: Each end user needs the interpreter and the program
Complier: Users need just the compiled program
Assembler: Users need just the compiled program - 116how does an interpreter, complier and assembler compare on: source code?Interpreter: End user can see the source code
complier: End user can’t see the source code
assembler: End user can’t see the source code - 117what are the main components of a computer?MAIN MEMORY (ram). Central processing unit (cpu), secondary storage (hard drive, ssd), input and output devices
- 118what does the cpu do?The CPU processes instructions, when you run a program, it is the CPU which runs the instructions, A CPU simply runs one simple instruction at a time, it carries out billions of instructions per second
- 119what is the stored program concept?Before about 1943, early computers stored the data to be worked on in memory. The program was not stored, Instructions were input one at a time using switches or read in punch cards and executed one at a time. In 1943-44 mathematician von Neumann and his colleagues had the idea of storing the program instructions as well as the data in the program. This was how the stored-program computer was made.
- 120what is the Von Neuman architecture?Program instructions and the data the programs are using are both stored in the same memory
The CPU accesses both instructions and data from the same RAM - 121what are the components of the CPU?Control Unit
Arithmetic-Logo Unit (ALU)
There are also registers that are used to carry out these operations
A register is a very fast memory location in the CPU itself
Cache is also located on the CPU - it is slower to access then the registers but faster than the RAM - 122why are registers used in the CPU?The CPU needs somewhere to stored small amounts of data and results that it is operation on so, it uses memory locations called registers
- 123how many bits each does a 8-bit CPU have?An 8-bit CPU will have registers that are each 8-bits
- 124what is an example of a calculation using the registers in the CPU?If you wanted to perform the calculation 5+2 you might do the following:
MOVE 5 into register1
MOVE 2 into register2
ADD register1 and register2 and store in register3 - 125what does the ALU do on the cpu?Performs two sorts of operations on data:
Arithmetic operations (Addition, subtraction, multiplication, division), Logical operations comparing one data item to another:
Is A > B , is X = Y for example. - 126what does the Control Unit do in the CPU?The control unit co-ordinates and controls all the activities taking place within the CPU, it decodes instructions and executes them, it receives signals from the system clock, it directs the timing and control of other parts of the CPU
- 127what does the clock in the CPU do?The clock controls the timing of the processor
It switches between 1 and o serval million times per second and synchronizes all CPU operations - 128what is the frequency clock?basically, the clock speed it is the number of clock cycles which each second (pic)
- 129what is a bus?A bus is a set of parallel wire connecting two or more components of the computer. When the CPU wishes to access a particular main memory location, it sends the address requested to the memory on the address bus, The data in that location is then returned to the CPU on the data bus, Control signals are sent along the control bus
- 130what are the three main computer buses?Address bus
Data bus
Control bus - 131what does the address bus do?carries memory addresses from the processor to other components such as primary storage and input/output devices. The address bus is unidirectional.
- 132what does the data bus do?carries the data between the processor and other components. The data bus is bidirectional.
- 133what does the control bus do?carries control signals from the processor to other components. The control bus also carries the clock's pulses. The control bus is unidirectional
- 134what is the main purpose of the computer buses?The main purpose for a data bus is to send control signals and data between the processor and other components.
- 135how is the CPU connect to external input-output devices?The CPU is also connected to the external Input-output device controllers by means of the system bus. Only one device can transmit along a bus at any one time. The address bus is one way only from the CPU
- 136what affects the CPU's performanceClock speed
Processor cores
Cach
- 137how does clock speed affect the cpu?The clock speed determines how quickly the central processing unit (CPU) can retrieve and interpret instructions (Cycles per second measured in hertz )
- 138how do processor cores affect the CPU?Having several processor cores have an advantage and that is that each core can handle a different data thread simultaneously, allowing for a much quicker transfer of data at any given time.
- 139how does cache affect the CPU?The larger the cache, the more instructions can be queued and carried out. Memory on the CPU that is faster than RAM but slower than registers
- 140why is the clock speed important for a computer?Everything in a computer happens on the pulse of the internal clock
Therefore, the faster the clock speed the faster instructions are processed - 141One cycle per second = 1 hertz (Hz) = 1 instruction carried out each second how many cycles is: 1 kilohertz (kHz) 1 Megahertz (MHz) 1 Gigahertz (GHz)1 kilohertz (kHz) = 1000 cycles per second
1 Megahertz (MHz) = 1,000,000 cycles per second
1 Gigahertz (GHz) = 1,000,000,000 cycles per second - 142how many processors does a dual core have and what does this mean?A dual-core processor has two processors in the same integrated circuit, linked together. A dual-core processor has the potential to perform two instructions at the same time. This allows twice as many instructions to be executed however it doesn’t always perform at this rate as software may not be able to take full advantage of both cores (as might be designed to just use one)
- 143what is cache memory?Cache is a small amount of very fast, expensive memory in the CPU
Program instructions and data that are fetched are stored in cache in case they are needed again soon
It can be accessed faster than regular main memory (RAM) - as RAM is further away from the processor than cache (pic) - 144What are the three cache levels ?Level 1 cache is extremely fast but small (between 2-256KB) located in the CPU
Level 2 it is very fast but a little slower than level 1 cache. The typical size is 256-8MB
Level 3 is the slowest type of cache is the slowest type of cache but still faster than RAM usually locations in CPU (pic slide 74) - 145what are the benefits of cache?The data used most often by the CPU is held in cache so is available extremely quickly. This greatly reduces the time that the CPU must wait for data from the main memory. However, the size of the cache is a major factor in determining the performance of the CPU
- 146by which three operations does the cpu operate? and what do they do?FETCH – causes the next instruction to be fetched from the main memory
DECODE– decodes the instruction to work out what the instruction is
EXECUTE – the instruction is executed
This process is then repeated - 147explain what happens in the FETCH part of the cycle in the cpupic
- 148explain what happens in the DECODE part of the cycle in the cpuPIC
- 149explain what happens in the EXECUTE part of the cycle in the CPUPIC
Informationen
- Beschreibung
- GCSE Computing (Computer Systems) Karteikarten am Computer Systems, erstellt von lucy hay am 02/11/2022.
- Erstellt von
- lucy hay
- Aufrufe
- 0
- Bewertung