1. Components of a Computer System
ADCs - Data Loggers
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2. Learning Objectives
State the difference between analogue data and digital data.
Describe the need for conversion between analogue and digital data.
Name the general name for devices which do this conversion.
Explain that a “data logger” converts analogue signals to digital so that computers can understand the data readings from sensors.
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3. Structure Diagram INPUT DEVICES MAIN MEMORY PROCESSOR OUTPUT DEVICES
AUXILIARY STORAGE
ROM
COMMUNICATIONS
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4. Communications
Sending and receiving data to and from other computers or devices.
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5. Analogue Data Analogue devices such as:
Clocks
Thermometers
Phones
Speakers
Represent variables by an analogous quantity or variations (modulations) :
Time is represented by the angle of the hands
Temperature is represented by the height of a column
Sound waves on a normal phone line or from speakers.
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6. Digital Data Computers work with data in a digital form.
Streams of 0's and 1's
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7. Need for conversion ADCs (Analogue to Digital Converters)
If computers are to receive or send analogue data (sensors, speakers, phone lines, etc…).
There must be conversion between analogue and the digital data computers use.
Devices which do this are called:
ADCs (Analogue to Digital Converters)
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8. Data Loggers Data Loggers
Convert analogue data from sensors to digital data which a computer can understand.
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9. Sound Cards Sound cards
Convert digital data to analogue data for speakers / headphones to use.
Convert analogue data from microphones to digital data which a computer can understand.
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10. Plenary What is the difference between analogue data and digital data?
analogous quantity or variations (modulations)
Time is represented by the angle of the hands
Temperature is represented by the height of a mercury column
Sound waves on a normal phone line and or from speakers.
Digital data:
Streams of 0's and 1's
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11. Plenary Why do we need to convert between analogue and digital data?
Computers work with data in a digital form.
What are devices that do this conversion called, can you name three examples and state when they are used?
ADCs (Analogue to Digital Converters)
Data Loggers - Convert analogue data from sensors to digital data.
Sound Cards - Converts digital signals to analogue data and for speakers to use and vice versa from microphones.
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12. Plenary
In which types of network is a modem necessary and unnecessary?
Modem needed:
WANs
Modems not needed:
LANs
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