Name:
Hardware
The OCR Specification says that you should be able to:
The Central Processing Unit
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state the purpose of the CPU
describe the function of the CPU as fetching and executing instructions stored in memory
describe cache memory
explain how common characteristics of CPUs such as clock speed, cache size and number
of cores affect their performance
Memory:
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describe the difference between RAM and ROM
explain the need for ROM in a computer system
describe the purpose of RAM in a computer system
explain how the amount of RAM in a personal computer affects the performance of the
computer
explain the need for virtual memory
discuss how changes in memory technologies are leading to innovative computer designs
Secondary Storage
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explain the need for secondary storage
describe common storage technologies such as optical, magnetic and solid state
describe flash memory
select suitable storage devices and storage media for a given application and justify their
choice
using characteristics such as capacity, speed, portability, durability and reliability
Innovative Computer Design
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discuss how changes in memory technologies are leading to innovative computer designs
Input and Output Devices
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understand the need for input and output devices
describe suitable input devices for a wide range of computer controlled situations
describe suitable output devices for a wide range of computer controlled situations
discuss input and output devices for users with specific needs
Binary Logic
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explain why data is represented in computer systems in binary form
understand and produce simple logic diagrams using the operations NOT, AND and OR
produce a truth table from a given logic diagram
Past Paper Exam questions
Jan 2011
1. Jo buys a notebook computer which has a 3MHz quad-core central processing unit (CPU).
(a) State the purpose of the CPU.
To carry out the processing on the computer/To (fetch and) execute instructions'
[1]
(b) Describe what is meant by
3MHz CPU
3MHz is the clock speed / how fast the processor is
Indicates how many instructions may be processed in each second
Indicates how many clock cycles per second
[2]
quad-core CPU
The computer has 4 cores
which are independent processors within the CPU
working simultaneously / can perform multiple tasks
[2]
2. A desk-top computer’s memory includes ROM and RAM.
Tick one box in each row to show whether each of the statements is true for ROM or RAM.
[3]
3. A shopping centre uses several remote-controlled CCTV cameras for security. An operator uses
a computer to watch, control and record the output of the cameras.
State an input, output and storage device which will be needed by the computer. For each, explain
the reason why it is needed.
Input device & Reasons
Joystick
 To control the CCTV cameras
 to zoom/tilt/pan
 as they allow precise movements (in 2 axis)
Keyboard
 To type commands into the system
 to perform complex control tasks
 Key presses can be used to control the cameras
[3]
Output device & Reasons
Monitor/Array of monitors
 Show the output of cameras
 Showing multiple cameras at a time
Printer
 To print hard copy images from the recordings
 eg to be used as evidence
[3]
Storage device & Reasons
hard disk drive with large capacity
 to record feed from all cameras
 simultaneously
 allows direct access to any part of the recording
rewritable large optical drive/removable flash storage
 to save recordings (eg for a given day)
 for archiving purposes
[3]