30-10-2012, 11:35 AM
Microcontroller based Digital Security System
ABSTRACT
The system comprises of a small electronic unit with a numeric pad, which is fixed outside the entry door to control a solenoid – operated lock simulated by stepper motor .When an authorized person enters, a predetermined number (password) is entered via the keypad, the stepper motor operates for a limited time to unlatch the solenoid and operated lock so that the door can be pushed /pulled to open. At the end of preset delay, the stepper motor de-energies and the door get locked again. If the entered password is wrong it gives a loner beep continuously. The system also comprises of four sensors in all four directions, so that if any person entering through corresponding sensor ,results in the display of that direction(east, west, south, north) on the LCD, along with a long beep.