Transcript StorageDevicesAndFurtureTechx

Storage
Devices
Understanding Computers
Understanding Computers
L5 – Storage Devices
Learning Objectives
• All will be able to describe how data is stored
on a CD
• Most will understand how modern
communication and computing devices
combine multiple technologies
• Some will discuss future uses of technology
and the pace of change (Moore’s Law)
Understanding Computers
L5 – Storage Devices
Data Units
Name
Bit
Byte
Kilobyte
Megabyte
Gigabyte
Terrabyte
Equal to
1 bit
8 bits
1,024 bytes
1,024 kilobytes
1,024 megabytes
1,024 gigabytes
Size in Bytes
1/8
1
1,024
1,048,576
1,073,741,824
1,099,511,627,776
Understanding Computers
L5 – Storage Devices
Storage Units
Name
Byte
What can it store?
A single letter, like "A."
Kilobyte
Megabyte
Gigabyte
A 14-line e-mail. A pretty lengthy paragraph of text.
A good sized novel.
Roughly 300 MP3s or 40 minutes of video at DVD
quality. A CD holds about three quarters of a gigabyte.
1,000 copies of the Encyclopedia Britannica.
Statistically, the average person has spoken about this
much by age 25!
Terrabyte
Understanding Computers
L5 – Storage Devices
Activity – Worksheet storage devices
Understanding Computers
L5 – Storage Devices
Optical Media
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CDs, DVDs, Blu Ray Disks
Some are read only
Some you can burn new data onto
Some you can re-use over and over again
with new data
Understanding Computers
L5 – Storage Devices
Reading and Writing to a CD-ROM
• Powerful laser
‘burns’ disk surface
• Laser ‘burns’ pits
into surface
• Weak laser reads
surface
• Detector measures
reflected light
Understanding Computers
L5 – Storage Devices
Tracks on a CD
• A CD has one long
track on it full of
Pits and Lands.
• This tracks begins
at the centre of
the disk and work
outwards in a
tight spiral.
Understanding Computers
L5 – Storage Devices
‘Burning’ a CD-ROM
• Pits and Lands are used to represent 1s and 0s in
Binary.
• Lasers shine light at the surface and light is reflected
from the silver surface of the disk – except where a Pit
begins or ends. Here the reflection is scattered and a
1 is read
– Good reflection / Poor reflection
– On / Off
– 1/0
• A pattern of 1s and 0s can make a word using ASCII,
therefore you can store a word using a series of Pits
and Lands ‘burnt’ into the disk.
Understanding Computers
L5 – Storage Devices
How a CD-ROM is read
Top of CD ROM Disk
Change
Pit
Change
Change
Land
Land
Pit
Land
Bottom of CD ROM Disk
Reflected Light
Laser
Light Sensor
• Data is encoded onto the CD using a
series of ‘Pits' and ‘Lands‘.
• A change from a Pit to a Land is read as a
1 and no change or a Land is read as a 0.
• In this figure, it will read as: 01001010
• Remember Your ASCII!
• Therefore 01001010 = 74 = Letter J
• 8 Bits = 1 Byte = 1 Character of Text
Understanding Computers
L5 – Storage Devices
The Surface of a CD-ROM
• Microscopic view of the surface of a CD ROM.
Understanding Computers
L5 – Storage Devices
Activity
• Complete Worksheet Reading from a CD.
• Convert the diagrams into binary and then
into denary numbers
Convergence and
New Technologies
Understanding Computers
Understanding Computers
L5 – Storage Devices
Timeline of Communication
Pre 1800
1838
Early 1800s
1896
1848
Understanding Computers
L5 – Storage Devices
Multiple Technologies…
Understanding Computers
L5 – Storage Devices
… Now fit into one device
Understanding Computers
L5 – Storage Devices
The Effect of Changing Technologies
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Connectivity
Convenience
Creativity & Design
Globalisation & Collaboration
Potential & Innovation
Research & Discovery
Understanding Computers
L5 – Storage Devices
Future and Emerging Technologies
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RFID?
Robotics?
Medicine?
Space Exploration?
Understanding Computers
L5 – Storage Devices
Future and Emerging Technologies
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Wireless Charging
Driverless Cars
Domestic Robots
3D Printers
RFID – Radio Frequency ID
Understanding Computers
L5 – Storage Devices
The possibilities of RFID?
– Your Mobile Phone might have a RFID Chip inside it
– Supermarket products may get RFID chips
– Your trolley may be automatically and instantly ‘read’ at
an RFID checkout
– Your mobile phone will pay for the goods remotely using
existing RFID touch technology
– Your fridge and cupboards could have RFID chips and will
recognise everything in them offering you suitable recipes
– Your bin could recognise when you have thrown away a
product and automatically re-order another for you
Understanding Computers
L5 – Storage Devices
The Information Age
• You are growing up in the Information Age
If you think you are suffering from information
overload then you might be right – [a study in
2011 showed] everyone is bombarded by the
equivalent of 174 newspapers of data a day.
The Daily Telegraph (Online) 11 Feb 2011
Understanding Computers
L5 – Storage Devices
What can your tech do now?
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How many Gb in your USB memory stick?
How many Gb memory in your mobile phone?
How many Megapixels in a digital camera photo?
How fast is your computer?
• What might it be in 2 years?
• What might it be in 10 years?
Understanding Computers
L5 – Storage Devices
Moore’s Law
Moore’s Law says that the number of transistors in
integrated circuit boards doubles every two years.
The capabilities of many digital electronic devices
are strongly linked to Moore's law: processing speed,
memory capacity, sensors and even the number and
size of pixels in digital cameras.
This means that a 32Gb memory chip now could be
1Tb memory chip in only 10 years if it doubles in
capacity every two years.
Understanding Computers
L5 – Storage Devices
The Pace of Change
• The pace of change in the field of technology
and every part of society it touches makes it
difficult to predict where things will be in even
10 years.
• Looking back at our recent past is dizzying in
terms of the development that has already
happened.
Understanding Computers
L5 – Storage Devices
Activity
• Create a poster, information sheet or leaflet
• Use the changing technologies worksheet to
give you titles and ideas
OR
• Pick one of the future technologies spoke
about and explain in detail what it is and how
it might be used.