Design and simulation of wall-cross detection security system using pic16f877a microcontroller

The world of today is highly integrated and depends on digital electronics especially in securities, communications, etc. in this thesis a security system was developed to look after four square walls north wall, south wall, east wall and west wall. Each wall has a sensor designed using light dependent resistor(LDR) and light emitting diode(LED) whenever somebody or something crossed the wall he/she blocked the light-dependent resistor(LDR) from receiving light from light emitting diode(LED) that makes the light dependent resistor(LDR) to output 0 volt to peripheral interface controller (the peripheral interface controller function as the brain of the thesis) whenever the peripheral interface controller detects 0 volt it send signal to liquid crystal display(LCD) to display that, that particular wall has been crossed, and the system will immediately rotate the dc motor that carries closed-circuit television(CCTV) camera to stop at the crossed wall in order to capture a real-time video and send to the buzzer. If the peripheral interface controller(PIC) detects 5 volts from all the walls light dependent resistor(LDR) that means that all the walls are not being crossed, if all wall light dependent resistor(LDR) output 5 volts the peripheral interface controller(PIC) will display on the liquid crystal display(LCD) "all walls ok". The system also displays a calendar (time and date) on liquid crystal display(LCD).