Ch 2 computer hardware
Give 3 uses of a RFID Reader
* identify products in shops *in airports to track luggage *to tag animals *to collect payments automatically in toll booths *to access car parks
Name the three main logic gates:
*NOT output will be the opposite of the input *AND the output will be 1 if both outputs are 1 *OR the output will be 1 if one outputs are one
Name three uses of speakers
*music *warning sounds *voice for communication *synthetic voice (created by software) for screen reader systems
Give 4 types of sensors
*temp. Sensor *water level sensor *light sensor *pressure sensor *accelerometer *motion sensor
What does the magnetic hard disk store?
*the operating system *installed programs *user data
Identify, w/ reason, 3 devices that would help a visually impaired person to use a computer
1) raised dots to identify symbols 2) speaker and voice synthesis to read documents 3) microphone w/ voice recognition to issue commands
Explain how an eye-Typer works
A camera tracks the movement of the user's eye and can detect which key the user is looking at. A slow blink is used to select the key to type commands into a computer system
Binary means
A system of numbers using only two digits; 0 and 1
How is a foot mouse operated?
A track ball device that can be operated with the foot
What is the most suitable type of secondary storage for: A) transferring work between home and school B) distributing a software application C) storing work and programs on a large school network D) storing images in a digital camera?
A) USB flash memory drive B) CD Rom C) hard disk drive D)flash memory card
State the two main components of the CPU
ALU Control unit
1 advantage and disadvantage of a dual core processor over a single core processor
Advantage: a dual core processor can process data simultaneously, so faster Disadvantage: a more complicated operating. System is needed; it is harder to write software for multiple processors
Actuators create physical movements in response to a computer command to control..
Aeroplanes, wheelchairs and robots
The arithmetic and logic unit (ALU) carries out..
All of the arithmetic and logical operations
RAM can be accessed and changed by the computer at..
Any time
A plotter reproduces large-scale engineering or..
Architectural drawings
Why are thermal printers used in EPOS systems?
Because they are low cost and quiet
The boot sequence contains the..
Boot loader - a program that starts this sequence when the computer is switched on
ROM contains the..
Boot program
ROM is small (1 or 2 MB required for the..
Boot program )
What is an eye-Tyler used for?
By ppl with limited physical mobility
Multi-core processors use multiple..
CPUs working together
The speed at which a CPU can process data depends on: CPU clock speed..
Cache memory Number of processor cores
Memory cards are used in..
Cameras
A sensor detects physical conditions and automatically..
Collects data
Logic gates can be combined to make more..
Complex circuits
Hardware describe the physical..
Components of a computer.. Anything that can be seen or touched
What does the mouse do?
Controls a pointer on screen that can be opened, dragged or controlled by clicking buttons on the mouse
Flash memory is used as a protea me medium for storing and transferring..
Data
RAM stores programs and..
Data being used by the computer
What are keyboards used for?
Data entry into a computer
What does volatile mean?
Data is lost when the power is turned off
What does non-volatile mean?
Data is retained when the power is turned off
How does the use of virtual memory affect the performance of a computer?
Data is swapped between RAM and the hard disk; hard disk access is slower than RAM access, which slows access to data; performance is slower because transferring data is slow
Microphone uses voice input for communication or to control the..
Device
The bob Neumann principle is the foundation of modern..
Digital computing. It uses binary values to store both data and instructions
The speed of the fetch- execute culture is determined by an..
Electronic clock chip
Cache memory is ex..
Expensive
Data that is in used transferred to cache memory to make access to it..
Faster
The Von Neumann architecture is the basis..
For all modern digital computers
Camera captures images or video eg..
For video conferencing or facial recognition
Processor speeds are typically measure in..
Gigs hertz, billions of cycles per second
A foot mouse can be used by ppl with limited..
Hand movement
Virtual memory is part of the h..
Hard drive
The boot sequence is a sequence of processes that contains all the..
Information and instructions to get the computer up and running.
What type of printers give high-quality photographic images?
Inkjet
Hand held device have a touch screen display for..
Input and output
Hardware components include..
Input, output, storage, and processing devices
Identify 2 input devices and 2 output devices on a mobile phone
Input: touch screen; buttons; microphone; camera Output: touch screen; speaker; motor( to make the phone vibrate)
A computer is of little value of it cannot accept
Inputs and provide outputs
What do touch screens allow the user to do?
Interact directly with icons or an on-screen keyboard to control the device
A puff-suck switch can be used by people with severely limited physical mobility by blowing..
Into or sucking on a small tube
What is the purpose of the CPU?
It carries out processing on the computer, it fetches and executes instructions
A Braille keyboard can be used by people with visual impairments to type text and commands into a computer system using..
Keys with embossed patterns that match the standard Braille characters
What are the most common type of monitors?
LCD and LED
RAM is la..
Large (4GB or more in a typical computer)
RFID reader: reads data from an electronic version of a barcode; does not require..
Line of sight
The disadvantage multiple-core processors is that more complicated operating systems are needed to..
Manage them
ROM is programmed during computer..
Manufacture
What types of printers give a fast economical output?
Monochrome or colour laser
How would installing extra RAM affect the use of virtual memory and what effect does this have on the performance of the computer?
More RAM means fewer data transfers to virtual memory and improved performance
A typical computer will have more GB of memory but will have less MB
Of cache memory
RAM contains the op..
Operating system
What is in RAM when the computer is working?
Operating systems; programs; data in use by programs
A barcode scanner reads light reflected back from a pattern of thin and thick lines that represent a a product code or..
Other identification number
Speakers produce sound..
Output
The clock speed is measured in cycles..
Per second, known as Hertz
Adding more RAM reduces the use of virtual memory and improves the..
Performance of the computer
Solid state drives are used in por..
Portable computers
What type of memory is cache memory?
Primary storage
The CPU carries out all the..
Processing in a computer
What does a printer so?
Produces hard copy on paper?
Computers are used to process data we supply in order to..
Provide us with the required output
Virtual memory is used as an extension to..
RAM
Virtual memory is used when the computer does not have enough..
RAM to hold all the data and programs required
All data and instructions are stores in..
RAM, as binary numbers
Why does a computer have both ROM and RAM
ROM is needed for the initial setting and boot sequence RAM is needed to store data and programs in use
Flash memory is a type of ROM that can be..
Rewritten
Why type of storage is flash memory?
Secondary
Cache memory has access times sim..
Similar to the CPU
An advantage of multiple core processors is that more data is processed..
Simultaneously
Access to virtual memory is..
Slower than to RAM
Hardrives are secondary..
Storage
Data and instruction are indistinguishable from each other and are..
Stores together in RAM
The architecture is the internal logical..
Structure and organisation of the computer hardware
Computers use binary values because it is easy to..
Tell the state of a switch (on/off) or (0 or 1)
What is meant by '2.5 MHz quad core' when describing a processor?
The CPU clock speed on 2.5 MHz (2.5 million instructions can be processed per second) It has 4 cores (4 independent processor working together)
The control unit uses electrical signals to control..
The flow of data within he CPU
After the boot sequence is completed, control is handed to..
The operating system to provide programs for the CPU to process
The CPUs can all fetch, decode and execute instructions at..
The same time
3D printer make..
Three dimensional objects
ROM is stores instructions and data required..
To start up the computer
Why is secondary storage needed?
To store data and programs when the power is switched off
Why does a computer need secondary storage?
To store data and programs when the power is switched off because RAM is volatile and loses contents when there is no power
What is cache memory used for?
To store data waiting to be processed
The CPU cannot access main memory at the same speed as the processor clock chip;...
Transferring day at from main memory causes significant delays
What is the most common way of displaying text, images and video?
Using a monitor
Data is passes between RAM and..
Virtual memory
RAM is vo..
Volatile
ROM is non..
Volatile