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Automatic Room Light Controller with

Visitor Counter

BYK. Immanuel (Roll No. 2011273009)

C. Jaganathan(Roll No. 2011273010)

ME - Applied Electronics (PT)

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Objective

To implement an automatic room light controller that automatically

makes glow the light when there is at least one person in the room.

Also this setup has an embedded LCD display module that displays

the visitor count in the room.

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Sections of the Project Power Supply

Sensor Setup

Microcontroller

LCD Display

Light Section

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Block Diagram

Microcontroller

Section

LCD Display

Power Supply

IR Trans-receiverSection

Light Control

Section

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Working Two IR LED & Photo-diode sensors are implemented at the entrance

of the room to sense the entry or exit of a person.

According to the action sensed the visitor count is increased or

decreased.

For counts greater than zero the light switches ON and the visitor

count reaches zero the light is switched OFF

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Power SupplyA Switch Mode Power Supply (SMPS) is used to convert 220v AC

supply into 5v DC suitable for the operation of the microcontroller.

The 5v DC supply is given as the Vcc and all the components of the

project, work in the 0-5v scale.

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Sensor Setup Two IR-LEDs act as transmitters and two photo-diodes act as

receivers.

The received sources are given to comparator for deciding whether

the light source is obstructed. first followed by Source 2 the action

sensed is incoming of a person.

Whenever Source 2 is obstructed first followed by Source 1 the

action sensed is outgoing of a person

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Sensor Setup LM 358

This is a comparator IC

This IC has two comparators

Two inputs and an output for each comparator

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Microcontroller

Atmel 89S52 microcontroller is used

The light controller is interfaced with Port 0

The sensor setup is interfaced with Port 1

The command/data-lines of the LCD module is interfaced with Port 2

The control-lines of the LCD module is interfaced with Port 3

Crystal Oscillator producing 11.0592 Mhz is used

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Microcontroller

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LCD Display Module 2 X 16 LCD Display is used

This LCD module has two line display each line is capable of

displaying 16 characters

8 command/data lines are available for sending command words or

data to be displayed in the LCD module

3 Control lines are available for performing operations like read/

write, reset, enable etc.

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Light Control In the prototype model a bright white high wattage LED is used as

the room light in order to make the kit portable

A transistor BC 547 is used to drive the glowing of the LED and also

cater to the current requirement for the LED

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Circuit Diagram

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Tools used Keil C Compiler

Progisp burning software

ISP, AT series USB burner kit

Languages Used: Embedded C.

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Advantages Saves current by switching OFF the light when no one is present in

the room

Displays number of persons inside the room at any time

Also gives information of total number of visitors who entered the

room

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