Report on final year project

CARD SWIPING AND PASSWORD

AUTHENTICATION SECURITY SYSTEM(CSPASS)

INTRODUCTION:

Card swiping and password authentication security system is a

security system involving a card swiping system after which a

password is asked for granting access into a particular authorized area.

DEVICES USED:

1. Microcontroller (AT89C52)2. Power supply 3. U-shaped opto coupler(MOC7811)4. Keys/push buttons(4 pin)5. Relay(HK3FF-DC12V-SH)6. Buzzer(SE B-20-B)7. L.C.D(JHD 162A)

External pull up resistors at pin 0

• Microcontroller pins can broadly be divided into 4 sets i.e. P0, P1, P2, P3.

• P0 pins are provided with pull up resistors externally because Microcontroller doesn’t have them internally.

• Pull up resistors are provided for current limiting in the data transfer.

• Reason for not using the other 3 pins being that they are dedicated for other functions like pin 3 is for interrupts.

CRYSTAL OSCILLATOR

• A crystal oscillator is an electronic circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency(11.0592 MHz in this case).

• This frequency is commonly used to keep track of time, to provide a stable clock signal for digital integrated circuits.

MICROCONTROLLER• 256 x 8-Bit Internal RAM• 32 Programmable I/O

Lines• Three 16-Bit

Timer/Counters• Eight Interrupt Sources

Programmable Serial Channel

• Low Power Idle and Power Down Modes

PIN DIAGRAM

POWER SUPPLY

POWER SUPPLY WORKING

• A center tapped step down transformer is used to convert 220V AC TO 12V AC.

• When the power is supplied to the circuit, an LED glows indicating the circuit is receiving power.

• The 12V AC is then converted to 12V pulsating (ripples) DC with the help of a bridge rectifier.

• Then this 12V DC is converted into 5V DC by a 7805 voltage regulator.

BRIDGE RECTIFIER WORKING• During +ve cycle, D2 and D4 conduct.• During –ve cycle, D3 and D1 conduct.

How to get a constant dc?1. A diode’s internal resistance is given by Ri.2. The time for charging of the capacitor is given by: T=2*Ri*C3. Ri and C both being small, the time taken for the capacitor to be

fully charged is very less.4. Thereafter, the next cycle starts after a slight bend of discharging

of the capacitor.

5. So, we obtain an almost straight line i.e. a D.C. which is constant.

U-SHAPED OPTOCOUPLER

• It consists of an IR emitting diode facing a photo detector in a molded plastic housing.

• A slot in the housing between the emitter and detector provides a means of interrupting the signal.

KEYS(MATRIX FORM)

• We have connected 12 keys (push buttons) in matrix form of 4 rows and 3 columns.

• 10 keys represent digits 0-9 and the remaining 2 are for entering or canceling the password.

RELAY:

• Dimension(L*W*H): 15.5 x 10.5 x 10.8

• Coil Voltage: 12V

• Max .Switching Voltage: 300VAC/60VDC

• Max Switching Power: 750VA /90W

• Coil Power: 0.5W, 0.2W, 0.36W

If the password is correct, then the LED starts glowing indicating that the relay is switched on.

BUZZER

• Sound: 85 db• Input: 1.5V-27V dc

– If the wrong password is entered thrice, then the buzzer starts ringing.

L.C.D.

•It is a 16*2 display which works on +5V power supply.

•Initially it displays ‘CSPASS BY CITM’.

•Then it displays ‘SWIPE CARD’.

•When the card is swiped, the display asks the user to ‘ENTER PASSWORD’.

•Whenever a key is pressed, a 'STAR SYMBOL' appears on display,so nobody gets to know what password is being entered.

LCD WORKING• When the password entered is correct, the

LCD displays ‘ACCESS GRANTED’. Also, the LED next to the relay starts glowing indicating that is on.

• When the password entered is incorrect, the LCD displays ‘WRONG PASSWORD’. On a wrong password being entered thrice, the buzzer starts ringing.

APPLICATIONS:

• Financial services • Affinity programs • Cellular phones • Set-top boxes • Secure network access