Project Title PASSWORD BASED CIRCUIT BREAKER CONTROL TO

Project Title PASSWORD BASED CIRCUIT BREAKER CONTROL TO ENSURE ELECTRIC LINE MAN’S SAFETY Under the Guidance of Submitted by

ABSTRACT ØThe microcontroller based door locker is an access control system that allows only authorized persons to access a restricted area. Ø The system is fully controlled by the 8 bit microcontroller which has an 8 KB of ROM for the program memory. ØThe password is stored in microcontroller can be changed at any time. ØA matrix keypad is interfaced to the microcontroller to enter the password while a relay driver IC is used to switch on loads through relays.

BLOCK DIAGRAM

HARDWARE REQUIREMENTS ØPOWER SUPPLY BLOCK ØMICROCONTROLLER (AT 89 S 52/AT 89 C 51) ØPUSHBUTTON ØLCD ØMATRIX KEYPAD Ø RELAY DRIVER Ø LED Ø 1 N 4007 Ø CAPACITORS Ø RESISTORS

POWER SUPPLY 230 V AC 50 Hz Bridge rectifier 5 v Regulator 5 V DC 12 V step down transformer Filter(470µf)

MICROCONTROLLER It is a smaller computer Has on-chip RAM, ROM, I/O ports. . . CPU I/O Port RAM ROM Serial Timer COM Port A single chip Microcontroller

INTERNAL STRUCTURE OF A MICRO CONTROLLER-AT 89 S 52/51 External interrupts Interrup t Control On-chip ROM for program code Timer/Counter On-chip RAM Timer 1 Timer 0 CPU OSC Bus Control 4 I/O Ports P 0 P 1 P 2 P 3 Address/Data Serial Port Tx. D Rx. D Counter Inputs

FEATURES OF AT 89 S 51/52 Compatible with MCS®-51 Products 8 K Bytes of In-System Programmable (ISP) Flash Memory Endurance: 10, 000 Write/Erase Cycles 4. 0 V to 5. 5 V Operating Range Fully Static Operation: 0 Hz to 33 MHz 256 x 8 -bit Internal RAM 32 Programmable I/O Lines Three 16 -bit Timer/Counters Eight Interrupt Sources Full Duplex UART Serial Channel Interrupt Recovery from Power-down Mode Watchdog Timer Dual Data Pointer

PIN DESCRIPTION

RELAY ØIT IS A ELECTRO MAGNETIC SWITCH ØUSED TO CONTROL THE ELECTRICAL DEVICES ØCOPPER CORE MAGNETIC FLUX PLAYS MAIN ROLE HERE

ØThe relay's switch connections are usually labeled COM, NC and NO: ØCOM = Common, always connect to this; it is the moving part of the itch. ØNC = Normally Closed, COM is connected to this when the relay coil is off. ØNO = Normally Open, COM is connected to this when the relay coil is on

KEYPAD Ø A keypad is a set of buttons arranged in a block or "pad" which usually bear digits, symbols and usually a complete set of alphabetical letters. If it mostly contains numbers then it can also be called a numeric keypad. Ø In order to detect which key is pressed from the matrix, the row lines are to be made low one by one and read the columns. Assume that if Row 1 is made low, then read the columns. Ø If any of the key in row 1 is pressed then correspondingly the column 1 will give low that is if second key is pressed in Row 1, then column 2 will give low.

RELAY DRIVER (ULN 2003) ØULN 2003 is a high voltage and high current Darlington transistor array ØIt consists of seven NPN Darlington pairs that feature highvoltage outputs with common-cathode Clamp diode for switching inductive loads. ØThe ULN 2003 has a 2. 7 k. W series base resistor for each Darlington pair for operation directly with TTL or 5 V CMOS devices. ØCurrent, Output Max: 500 m. A ØVoltage, Input Max: 5 V ØVoltage, Output Max: 50 V

Fig: ULN 2003

LIQUID CRYSTAL DISPLAY (LCD) ØMost common LCDs connected to the microcontrollers are 16 x 2 and 20 x 2 displays. ØThis means 16 characters per line by 2 lines and 20 characters per line by 2 lines, respectively. ØThe standard is referred to as HD 44780 U, which refers to the controller chip which receives data from an external source (and communicates directly with the LCD.

LCD BACKGROUND ØIf an 8 -bit data bus is used the LCD will require 11 data lines (3 control lines plus the 8 lines for the data bus) ØThe three control lines are referred to as EN, RS, and RW ØEN=Enable (used to tell the LCD that you are sending it data) ØRS=Register Select (When RS is low (0), data is treated as a command) (When RS is High(1), data being sent is text data ) ØR/W=Read/Write (When RW is low (0), the data written to the LCD) (When RW is low (0), the data reading to the LCD)

Working of project ØThe numbers pressed in the matrix keypad load corresponding logical state at the input i. e. , port 1. ØThe program is so returned that when 1111 is pressed it switches ON load 1 & while 2222 is pressed it switches ON load 2 and so on through a relays interfaced through relay driver IC from the MC output

SOFT WARE REQUIREMENTS Keil an ARM Company makes C compilers, macro assemblers, realtime kernels, debuggers, simulators, integrated environments, evaluation boards, and emulators for ARM 7/ARM 9/Cortex-M 3, XC 16 x/ST 10, 251, and 8051 MCU families. Compilers are programs used to convert a High Level Language to object code. Desktop compilers produce an output object code for the underlying microprocessor, but not for other microprocessors.

i. e the programs written in one of the HLL like ‘C’ will compile the code to run on the system for a particular processor like x 86 (underlying microprocessor in the computer). For example compilers for Dos platform is different from the Compilers for Unix platform So if one wants to define a compiler then compiler is a program that translates source code into object code.

BIBILOGRAPHY Ø “The 8051 Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education. Ø ATMEL 89 S 52 Data Sheets. www. atmel. com www. beyondlogic. org www. wikipedia. org www. howstuffworks. com www. alldatasheets. com