Input, process and output

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Input, process and output

• When considering electronic systems we can say
  that it is made up of 3 main parts.
• Input
• Process
• Output

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Definitions

• Data has to flow into the system in some form.
• INPUT is the data flowing into the system from
  outside

• The next stage in the information flow is the
  input data being manipulated in some way.
• PROCESSING is the action of manipulating the
  input into a more useful form.

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Definitions

• The final stage in the information flow is
  normally to present the information.
• Output is the information flowing out of the
  system.

• Example
• Calculator
• Input keypad
• Process Microprocessor
• Output Display

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Definition

• A transducer is a device which converts an input
  signal into an electrical signal or an electrical
  signal into an output signal.
• Examples a microphone converts sound energy
  into electrical energy and a loudspeaker converts
  electrical energy into sound energy.

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Analogue and Digital Signals

• An analogue signal can have any value in the
  range.

• A digital signal appears as a square wave where
  values are either on or off, 1 or 0, high or low.

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Input Devices

• Microphone changes sound energy into electrical
  energy. It is an analogue device.

• Thermocouple consists of two wires twisted
  together to form a junction. When the junction
  is heated a small voltage appears.
• Thermocouples change heat to electrical energy.
• Heat to electrical energy. Analogue device.

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Input Devices

• Solar Cell semiconductor which produces a
  voltage when light falls on it.
• Light to electrical energy.
• Analogue device.

• Thermistor device which changes its resistance
  depending on the temperature.
• Used as a temperature control device.
• Analogue device.

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Input Devices

• Light Dependent
• Resistor (LDR)
• Device which lowers its resistance as
  temperature increases.

• Switch Used to open/close a circuit to
  stop/start the flow of current.

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Input Devices

• Voltage Divider

• Capacitor