MICROCONTROLLER BASED DIGITAL CODE LOCK

31 PAGES (4726 WORDS) Computer Engineering Project
ABSTRACT
Security is a prime concern in our day-today life. Everyone wants to be as much secure as possible. An access control for doors forms a vital link in a security chain. The microcontroller based Door locker is an access control system that allows only authorized persons to access a restricted area. The system is fully controlled by the 8 bit microcontroller AT89C2051 which has a 2Kbytes of ROM for the program memory. The password is stored in the EPROM so that we can change it at any time.
The system has a Keypad by which the password can be entered through it. When the entered password equals with the password stored in the memory then the relay gets on and so that the door is opened. If we entered a wrong password for more than three times then the Alarm is switched on.
When we go inside and come back then the microcontroller will sense the person using the Laser light, the microcontroller will automatically open the door for you.

CHAPTER ONE
INTRODUCTION…………………..4

CHAPTER TWO
PROJECT DESCRIPTION…………...…5
BLOCK DIAGRAM……………………...…5
BLOCK DIAGRAM EXPLANATION……………………5
CIRCUIT DIAGRAM…………………..11
MAIN CIRCUIT DIAGRAM……………………………11
POWER SUPPLY……………………………………..12
CIRCUIT EXPLANATION………………………………...12

CHAPTER THREE
FLOW CHART.…… ………………………13

CHAPTER FOUR
PROGRAM…………………………...14

CHAPTER FIVE
COMPONENTS DETAILS…………….…22

CHAPTER SIX
RESISTOR……………………………………..22
CAPACITOR…………………………….….22
TRANSISTOR………………….…...23
DIODE…………………………………………23
INTEGRATED CIRCUITS…………………….……...24

CHAPTER SEVEN
CONCLUSION……………………………….30
APPLICATIONS………………………………30
FUTURE ENHANCEMENT……………..30
REFERENCES……………………..……31

INTRODUCTION
Password Based Door Security System using Microcontroller” is used in the places where we need more security. It can also used to secure lockers and other protective doors. The system comprises a number keypad and the keypads are connected to the 8 bit microcontroller AT89C2051. This is one of the popular Microcontroller. It has only 20 pins and there are 15 input/output lines. The microcontroller has a program memory of 2 Kilobytes. The microcontroller continuously monitor the keypad and if somebody enters the password it will check the entered password with the password which was stored in the memory and if it they are same then the microcontroller will switch on the corresponding device.The system will allow the person who knows the password and it will not allow who don’t know the password and the system will also show the persons who try to break the protection barrier.