MICRO CONTROLLER BASED CODE-LOCK WITH EMERGENCY DAIL UP

This is microcontroller 8051 based code lock system which is operated by 4x3 matrix keyboard. If the user enters the correct password it opens the lock. Or if an unauthorized user tries to open with hit & try method, after three wrong tries it starts an siren & dials out the preprogrammed number to destination required & delivers the security message. The siren can only be stopped by entering the known password again, otherwise it will continue.