Transcript Document

Input, process and
output
• When considering electronic
systems we can say that it is
made up of 3 main parts.
• Input
• Process
• Output
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.
Definitions
• The final stage in the • Example
information flow is
normally to present
the information.
• Output is the
information flowing
out of the system.
• Calculator
Input – keypad
Process –
Microprocessor
Output – Display
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.
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.
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.
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.
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.
Input Devices
• Voltage Divider
• Capacitor