HOME/ OFFICE SECURITY SYSTEM (8051 BASED)

HOME/ OFFICE SECURITY SYSTEM (8051 BASED)
SECURTY IS A MATTER OF GREAT CONCERN TO ALL OF US IN THIS WORLD. NORMALLY THERE ARE FOUR TYPES OF SECURITY THREAT TO OUR PROPERTY. 1 )FROM THIEF, AN INTURDER. 2) FROM FIRE, SO WE USE FIRE SENSOR.3) WATER SPILAGE /OVER FLOW, SO WE USE WATER SENSOR. 4) GAS LEAK , WE USE GAS SENSOR, WHEN EVER THERE IS SECURITY BREACH FROM ONE OF ABOVE OR ANY COMBINATION OF ABOVE. THE PROJECT TAKES THE FOLLOWING ACTION .1) SOUNDS AN SIRON TO ATTRACT YOUR OR PUBLIC ATTENTION . 2) IF THE RESET SW IS NOT PRESSED WITHIN 30 SECONDS THE PROJECTS TAKES FURTHER ACTION, IT DIALS OUT PRESTORED NUMBER AND DELIVERS AN EMERGENCY MESSAGE STORED IN SPEECH IC. THE DIALING OUT CONTINEWS TILL A PERSON COMES AND PRESS THE RESET SW MAKING THIS SYSTEM FOOL PROOF. YOU CAN EVEN STORE YOUR MOBILE PHONE NUMBER. THE PROJECT PRESENTED HERE IS BASED ON WORLD’S MOST POWERFUL INTEL’S MCS-51 FAMILY OF MICROCONTROLLER ATMEL AT89C51. OPERATION: AFTER THE USER START THE SYSTEM BY PRESSING SW1 TO SWITCHON THE SYSTEM. SYSTEM START MONOTORING ALL FOUR SENSORS. PORT0.0 TO PORT0.3 THESE FOUR LINES ARE CONNECTED WITH OUR FOUR SENSORS. WHENEVER ANY SENSOR GET ACTUATED THE PERTICULAR PIN WILL BECOME LOW AND FOLLOWING WILL HEPPEN:- 1)P2.7 WILL GO HIGH ,TRANSISTER T3 WILL BECOME ON AND RELAY RL2 WILL SWITCH ON 12V POWER FOR SOUND SECTION. 2)P2.6 WILL BECOME HIGH AND M1 ON API8208 WILL BECOME HIGH SIRON WILL BE PLAYED THROUGH SPEAKER FOR THIRTY SECONDS. 3) IF THE USER DO NOT PRESS SW2 RST SWITCH BEFORE THIRTY SECONDS 4) P2.6 WILL BECOME LOW AND THE SIRON WILL STOP. 5) P2.5 WILL BECOME HIGH AND EMERGENCY MESSAGE WILL START SINCE M2 WILL BECOME HIGH. 6) P2.0 WILL BECOME HIGH AND OFF- HOOK RELAY WILL OPERATE THROUGH TRANSISTER T1 BC 548. THIS IS EQUIVALENT TO LIFTING THE HANDSET FROM THE RECEIVER. 7) AFTER 5 SECONDS P2.4 WILL BECOME HIGH AND TRANSISTER T2 WILL BECOME ON GIVING TWO SECOND DIAL PULSE ON THE TELEPHONE CIRCUIT ON THE REDIAL POINT 8) PRESTORED NUMBER WILL BE DIALED OUT. WHEN THE RECEIVER LIFTS THE HAND SET HE WILL GET THE EMERGENCY MESSAGE. THE MESSAGE WILL BE PLAYED FOR 30 SECONDS AND IT WILL STOP 9) OFF HOOK RELAY WILL DE-ENERGISE. 10) RELAY RL2 WILL BECOME OFF 11) THE PROCESS 1 TO 10 WILL BE REPETED UNTILL RESET IS PRESSED SENSORS: A)SMOKE SENSOR IS BASED ON OPTOMETRIC PRINCIPLE WHEN NO SMOKE IS PRESENT CLEAR LIGHT FALLS ON LDR ITS RESISTANCE REMAINS LOW AND TRANSISTER REMAINS IN CUTOFF STATE. COLLECTOR REMAINS HIGH.WHEN SMOKE IS PRESENT LIGHT GET OBSTRUCTED BY SMOKE RESULTING INCREASE IN LDR RESISTANCE TRANSISTER GETS ENOUGH CONDUCTING VOLTAGE AT ITS BASE AND BECOMES ON ,COLLECTOR VOLTAGE DROPS TO LOW IS AN INPUT TO MICROCONTROLLER PORT PINS. SENSITIVITY CAN BE ADJUSTED USING VR1 VARIABLE REGISTER. B) WATER SENSOR :-WHEN BOTH PROBES ARE EMMERSED IN WATER BASE GET ITS BIASING VOLTAGE THROUGH WATER AND TRANSISTER CONDUCTS, MAKING COLLECTOR LOW C) STRONG IR TRANSMITTER AND RECEIVER IS USED AS INTURDER SENSOR .AN IR INVISIBLE 36KHZ S BEAM IS SUFFICIENTLY AMPLIFIED IN TX MODULE WHEN THE RECEIVER CONTINEUSLY RECEIVE IR BEAM ITS OUT PUT IS HIGH. WHENEVER THIS BEAM IS OBSTRUCTED A LOW PULSE IS OUTPUT & IS CONNECTED TO MICROCONTROLLER SENSOR INPUT PIN . IR RANGE IS 15 TO 20 FEET. D) GAS SENSOR 'S ELECTRONIG CIRCUITORY GIVES LOW OUT PUT WHENEVER GAS IS DETECTED.