The “SMART CONTROLLER” is a combination of three applications,these are visitor counter,roomlight controller and automatic shutdown doors.Smart controller can be used in offices as well as home applications.For visitor counter light dependent resistors object counter can be installed at the entry gate to count the total number of people entering any venue. For example, it can be used at the railway stations or bus stands to count the people arriving per day or week. To make an object counter we can use a simple dark detector circuit and a normal seven segment display. Pole and NO (Normally Open) terminals of a relay have to be connected to the two pins which are used to activate ‘=’ key of seven segment display. As we block the light falling on LDR the LCD starts displaying counting.

Counters with directional detection are useful for counting of objects moving along a predefined path. These may find application as visitor counters and also for counting of objects in a given direction and ignoring those moving in the reverse direction. Here we present a simple circuit that counts the number of persons or the objects entering the premises ignoring those exiting or leaving it.On the other hand the roomlight controller is device through which the electrical energy is saved as the lights of room remains off till no one is in the room and if a person enters in room the lights automatically turns on and switched off when everyone left the room.This can be use in public places like railway station,bus stands,etc.The roomlight controller is connected to visitor counter as a person enters counters count and light controller switch on lights.In the same way when everyone get out of the room,the doors automatically shutdown as visitor counter shows null reading.

Circuit Diagram:-

Working :-

This Project Automatic Room Light Controller cum Automatic Doors Shutdown with Visitor Counter using Microcontroller. It is a reliable circuit that takes over the task of controlling the room lights as well us counting number of persons/ visitors in the room very accurately. When somebody enters into the room then the counter is incremented by one and the light in the room will be switched ON and when any one leaves the room then the counter is decremented by one. The light will be only switched OFF until all the persons in the room go out and doors also get closed at the same time and it will open again when visitor counter sensor is passed by someone. The total number of persons inside the room is also displayed on the seven segment displays.
The microcontroller does the above job. It receives the signals from the sensors, and this signal is operated under the control of software which is stored in ROM. Microcontroller AT89S52 continuously monitor the Infrared Receivers, When any object pass through the IR Receiver's then the IR Rays falling on the receiver are obstructed , this obstruction is sensed by the Microcontroller.Basically microcontroller is a device often regarded as mini computer as it has a 4-bit microprocessor which work as central processing unit for the microcontroller.The other devices like LDR and LED provides the necessary functioning of the counter.


1 This circuit is so cheaper and easily affordable.

2 Small in size & good stability.

3 It can be used in railway station, airport, office and industry for counting the person, etc.

To get source code mail at


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