Exam Prep Flashcards
Describe the usage characteristics and os of handheld devices.
Commonly known as smartphones and tablets. Single user, multitask, portable. Android and ios
Describe the usage, characteristics and os of minicomputers.
typically used as highpowered servers by large companies.
designed as 24/7 servers for databases, web and file storage applications.
Physically rack or tower mounted configurations the size of file cabinets.
kept in air conditioned rooms
operating systems - linux, Unix, windows server OS
List the seven main components of CPU.
- ALU - arithmetic and Logic unit
- FLU - floating point unit
- Registers
- BIU Bus interface unit
- Control unit
- Fetch Decode Unit
- L1 split cache, L2 and L3 unified cache
Describe the ALU in detail
The ALU performs two types of operations
1. Arithmetic operations such as multiplication, subtraction and division on integer numbers
2. Logical operations such as and, or, not and xor
receives operations from CU, takes data from the registers and performs the operations.
Describe the FPU in detail
Also called the maths coprocesser.
Performs maths on real numbers
Faster than the ALU for processing real numbers.
Define analog and digital signals.
analogue signal: Varies continuously and smoothly and represents data in its natural form.
Digital signal is a set of numbers that represent the strength of a natural signal at regular intevals.
Varies instantaneously and is not smooth.
What are the advantages of digital signal transmission over analog transmission
Less errors since uses distinct values ie 0 & 1 More efficient transmission Higher maximum transmission More secure (easier to encrypt Easier to integrate audio/Video/Data.
Discuss DRAM
DRAM - 1 transistor and 1 capacitor. Slower speed than SRAM Relatively cheap. Used in DIMMs and SIMMS. REquires peroidic dataq refresh every 2 ms
Discuss SRAM
4-6 transistors. Fastest memory type. Most expensive. Used in CPU registers and cache.
No periodic data refresh required.
Describe rendering
The rendering process is the process of converting a 3D image and representing the 3D image on screen to allow the viewer to perceive it as such.
What are the 7 steps to the rendering process
- Wire frame construction - objects outlined as a wireframe.
- Z-sorting. Objects drawn are placed in order from front to back. Alternative is z-buffering where only the pixels that will be visible are drawn.
- Lines in the wireframe that will not be visible are deleted.
- Shading the surfaces are shaded.
- Perspective correction:The image is adjusted to provide the illusion of perspective.
- Alpha bending: shading is adjusted for various light conditions.
- Fogging or depth cueing - used to enhance the illusion of distance.
Describe AM
In AM , the amplitude (size or voltage level) of the wave changes, depending on whether a 1 or a 0 is to be transmitted. The frequency and phase remain constant.
Describe FM
In FM, the frequency of the signal (that is the pitch or tone of the sound) is modulated. The result is that the frequency changes slightly (or “wobbles”) depending on the bit value being represented. The amplitude and phase of the signal do not change.
Describe PM
Instantaneously alters phase position of signal
Amplitude and frequency remain constant
Digital only technique
1 to 1 and 0 to 0 no change, 0 to 1 and 1 to 0 phase change
Describe Frequency
Frequency is the number of waves in an analogue signal that occur per second
Measured in hertz
Think of frequency as being like counting waves at the beach.
Describe Band
A band is a range of frequencies (i.e. the FM radio band covers the range of frequencies from 80MHz to 108 MHz).
Describe Bandwidth
Bandwidth is the width of the band
The difference between the highest and lowest frequencies in a band.
In networks, bandwidth is used to refer to the amount of data that can be sent per second.
Describe Baud Rate
Baud rate is the number of times that a signal changes in one second
Describe Bitrate
Bit rate is the number of bits of data sent every second
Measured in bits per second
Describe CAV
Constant angular velocity. For magnetic storage.
Measured in revolutions per minute
Disk always spins at the same speed
A sector of data takes up a larger length of track at the outside of the disk than at the inside of the disk.
This is compensated for by having more sectors near the outside of the platter.
Technically easier and cheaper to make a disk drive that spins at CAV
Describe CLV - Optical
MEasured in distance per second
Disk spins slower when reading from the outside of the disk and faster when reading from the centre of the disk.
A block of data is the same length of track regardless of where it is stored on the disk surface, hence constant linear data density.
More difficult to make a disk drive that spins at CLV because of the variable speed.
Describe USB
Universal serial Bus Provides data and power connection. 2. connection types - type A host device (supplies power) type B usually the peripheral divice 127 devices can be daisychained. Supports hotswapping and plug n play
What are the different speeds for USB
USB 1- 1.5 Mbps (keyboard mouse) USB 1 12 Mbps (printers etc USB 2.0 480 Mbps USB 3.0 5 Gbit/s Blue color USB 3.1 10 Gbit/s Blue Color
Firewire
Speed up to 800 Mb/s 4.5m max cable length Serial connection 63 devices daisychained. Hotswapping and Plug n play internal and external Different versions: Firewire 400 - 4 pin Firewire 800 - 9 pin Power supply and data
What are the advantages of a robot?
Cheap to run Work 24/7 Hazardeous enviornments Precise and repeatable Don't get bored Don't unionise
Disadvantages of robots
Expensive to reprogram
Currently only designed for specific takes
Hard to problem solve
Expensive setup and service.
What is a logical operation?
compare two logical statements.
What is a logical statement
A logical statement can either be True or False.
What is a logical expression?
Two logical statements are combined using a logical operation.
What is sequential access memory accessed?
Data accessed in chronological order.
Whats a characteristic of DRAM?
Needs periodic refresh.
What is random access memory?
Data can be accessed in any order
What is a charateristic of SRAM
Usd in CPU registers and Cache
What is Mask ROM?
Oldest type of ROM
What is EPROM
Clear quartz “Window” for erasing with UV light
What is flash ROM?
USB Stick drive
What is PROM?
Programmable once by the user
What is Trinitron?
Oval holes in shadow masks.
What is Triad?
Circular holes in shadow masks
What is LCD?
Light is twisted between polarised filters.
What is plasma?
Phosphor coating each subpixel
describe RISC?
Sleek simple design
Describe CISC
Backwards compatible
Describe Superpipeline
Longer pipeline with more and shorter stages
Describe Superscalar
Multiple pipelines working in parallel.
