Controlling the room lights as well as counting number of persons/visitors in the room very accurately.

Somebody enters into the room then the counter is incremented by one and the light in the room will be switched ON.

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.

The total number of persons inside the room is also displayed on the seven segment displays.

INTRODUCTION

Components

Components

IC7805 Micro-ControllerInfra Red LED

NE555 TimerLED

Block Diagram 

Bi Directional visitor counter system uses the logic of sensors.

Infra Red Sensors are used to check if someone is entering or going to

outside.

Here We are connecting the sensors in Through Beam Configuration.

As a person enters the data will be incremented on Segment display and

when somebody is going to outside the data will decrement.

And according to the value on display unit the appliances of room will be

controlled. For 0 value all appliances will be off and for less than 5 one

appliance will be on and for more than one 2 will be on.

Technology & Working

Circuit Diagram

NE555 Timer IC LCD (16*2) Microcontroller ( AT89s52) Frequency Crystal (11.0592 MHz) Capacitors Voltage regulator (7805) IR Sensors(TSOP17) Relay Resistors 104,33pF

FLOW CHART

The AT89C52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory.

The device is manufactured using Atmel’s high density non volatile memory technology and is compatible with the Industry-standard 80C51instruction set and pin out.

The on-chip Flash allows the program memory to be reprogrammedin-system or by a conventional nonvolatile memory pro- grammar. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the

Atmel AT89C52 is apowerful microcontroller which provides a highly-flexible and cost-effective solution to manyembedded control applications.

Microcontroller(AT89C52)

1. 8 KB Reprogrammable flash. 2. 32 Programmable I/O lines. 3. 16 bit Timer/Counter—3. 4. 8 Interrupt sources. 5. Power range: 4V – 5.5V

7. Fully static operation: 0 Hz to 33 MHz

9. Power off flag

11. Low power idle and power down modes 12. Interrupt recovery from power down modes 13. 256 KB internal RAM

 

• FEATURES:-

Gather input from various sensors . Process this input into a set of actions . Use the output mechanisms on the

Microcontroller to do something usefull.

working

05/03/2023Er. Mandeep Singh 12

Pin Description: Pin Symbol I/O Description

1 Vs - Ground2 Vcc - +5 V3 VEE - Contrast control4 RS I Register Select5 R/W I Read/Write 6 E I/O Enable7 DB0 I/O 8 bit data bus8 DB1 I/O 8 bit data bus9 DB2 I/O 8 bit data bus10 DB3 I/O 8 bit data bus11 DB4 I/O 8 bit data bus12 DB5 I/O 8 bit data bus13 DB6 I/O 8 bit data bus14 DB7 I/O 8 bit data bus

05/03/2023Er. Mandeep Singh 13

LCD Interfacing:

16X2 LCD Module

What is relay?

A relay is a automatic device which senses an abnormal condition of electric circuit and closes its contacts

OPERATING PRINCIPLE There are really only two fundamentally different operating principles, 1. Electromagnetic attraction 2. Electromagnetic induction Electromagnetic attraction relays operate by virtue of a plunger being drawn into a solenoid. Electromagnetic induction relays use the principle of the induction motor whereby torque is developed by induction in a rotor.