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Describe the following terms:Distributed, Reactive.

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Distributed:
•Embedded system may be a part of larger system.
•Many no. of such distributed ES from a single large embedded control unit.
•Each of the ES are independent embedded unit but they work together to perform the overall function.
•Ex: ATM Machine contains a card reader embedded unit responsible for reading and validating the user’s ATM card.
•A currency counter for dispatching currency to the authorized person.
•A printer unit for printing the transaction details.

 Reactive:
•ES are in constant interaction with a real world through sensor and user defined devices which are connecting to the input port of system.
•Any change happening in real world or an event are captured by the sensor or input devices. In real time and the control algorithm running inside the unit reacts in a designed manner, to bring the control output variable to the desired level.

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