A 4x3 framework keypad and a 16x2 LCD have been utilized here. Keypad and LCD are exceptionally regularly utilized enter & yield units, separately. A four digit predefined watchword should be specified the user. This secret word is saved in the framework.
While unlocking, if the dropped in watchword from keypad matches with the archived secret key, then the lock opens and a note is shown on LCD. Moreover a yield bind is made elevated to be utilized for further reason.
The associations in the circuit are as taking after: port P2 of microcontroller AT89C51 is utilized as information include port which is joined with information binds (7-14) of LCD. P1^0, P1^1 and P1^2 binds of microcontroller are joined with control binds RS, RW and EN of LCD. Port P0 is utilized to take include from keypad. P0^7 has been utilized as lock yield bind of controller.
As the project begins, string ‘Enter Password’ is shown on LCD. The keypad is checked for pressed digits one by one. Unfailingly, column and section of the nexus pressed is located and a ‘*’ is shown on LCD relating to the dropped in number. When the four digits are dropped in, the user is incited to ‘Confirm Password’ and again the info is taken through LCD. Depending on if the passwords don't match, a note is shown to demonstrate ‘Wrong Password’; generally the user is incited to unlock the apparatus.
To unlock, user should ‘Enter Password’ through keypad. Again the keypad is examined for pressed keys and comparing digits are distinguished. The passkey is shown as ‘****’ on the LCD screen. When the four digits are dropped in, they are contrasted and the pre-set watchword. Provided that every last trace of the four digits match with set watchword, LCD presentations ‘Lock Open’ and the lock yield bind goes elevated. Depending on if the security code is wrong, ‘Wrong Password’ is sent to be shown on LCD. The framework inches toward getting bolted if more than several endeavors are made with wrong secret key to open the electronic bolt. The framework should be reset in quite an impressive case.