7.1.2+Outline+the+uses+of+microprocessors+and+sensor+input+in+control+systems.

The role of the microprocessors in control
A microprocessor (a.k.a. CPU) is a computing engine assembled in one chip. It performs all the calculations and data processing of the computer.


 * **Having a microprocessor in a control system has several advantages:**
 * They can process data very quickly and much faster than a human could
 * Due to these fast speeds they can react very quickly to change in the control system
 * Control systems can run through out the year 24/7
 * They can work in places where it would be dangerous for a human to
 * Outputs are consistent and error free

However there are several disadvantages
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 * It may cost a lot of money to develop the software for a control system as they are specialized
 * The system will not be able to run in the case of a power shortage
 * The system will not be able to run in the case of a computer malfunction
 * A computer can't react to events that it has not been programmed for, unlike a human could
 * It can cause some concern if total control for a system and the decisions are handed over to a computer || [[image:http://orwellsfuture.com/wp-content/uploads/2011/02/microprocessor1.jpg width="170" height="143"]]


 * == The role of a sensor in a control system ==

Sensors are input devices that measure physical quantities in analogue data. There are sensors for a lot of conditions such as temperature, pressure, sound, humidity. They will send this signal to the CPU, after a ADC. For example:
 * A temperature sensor in a building to maintain a specific temperature.
 * A security alarm system may have infra-red and pressure plates to sense movement in an environment.
 * Magnetic sensors are used to detect metal and can be placed in roads to monitor traffic flow. || [[image:http://www.blogcdn.com/www.engadget.com/media/2011/06/trimount-tower-sensors.jpg width="225" height="225"]] ||

What is an ADC
An Analogue to Digital Converter, converts analogue data, from senors, to readable data for a computer, which is digital data. A computer can't read analogue data because it is constantly changing, so and ADC will sample data, losing a lot of quality but making it possible for a computer to process it.

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