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Project tested and working perfectly

Digital Lock Using AT89C2051 with LCD and Keypad - Assembly

A Brief Description:
This project is a rewrite of previously made project "Digital Code Lock using keypad and LCD"
I got many requests from student's side who want this project in Assembly language. So i spent some time making this project.

You will find working of this project same as that of original project. Nothing has been changed as such.

Its a simple project with efficient hacking prevention from Brute Force etc. The basic user lock is of 5 Digits and Master Lock is of 10 digits so its not easy for an intruder to break the lock unless you keep the code simple.
The input is taken from a 4x3 Keypad (please see the schematic for more information) and Display the user input on a 2x16 LCD. A pin is assigned as output for activating and deactivating the lock. For demonstration i have connected an LED to that pin.

User Side working:
The user has two options either he/she can use its own 5 digit code or use the default 5 digit code. If user has to do setup his own code, then he has to enter "12345" and press '#'. After this.. controller will ask for 10 Digit master password which is preprogrammed in the controller. Entering master lock, user can enter the new 5 digit code for the lock and press '#' to save it.

Using the Keypad:
Keypad has 12 keys (4x3) starting from 1,2,3,4,5,6,7,8,9,*,0,# (please see the schematic for layout). Numeric keys are used for entering numbers. '*' is used as the Cancel key and '#' is used as the Enter key.

Download File Information:
LCD.asm - Project Code
LCD.hex - Final Hex file
Digital Code Lock Schematic - PDF file of orcad schematic

If any problem Please post in the forum

17.46 kB





30 Oct 2014: 11:54 AM
i want you to help me in a program for interfatcing hex key pad with8051 and then make a digital lock
Kindly guide me as to how to combine the two different programs. thanks
02 Nov 2014: 07:10 AM
Just down the project and go through the code yourself. If you need help, just post a question. You can also look into our tutorial section for keypad tutorial.
24 Apr 2015: 18:24 PM
sir in the above shown program where are you going to dtore new password.
as you have not shown any memory ic
29 Apr 2015: 18:55 PM
@navig, This project does not store password in non-volatile memory. It just stores the password in RAM and if controller resets password also resets. You can add an EEPROM to add saving password to EEPROM.
Muhammad Ahmad
05 May 2016: 11:50 AM
Sir. kindly upload the proteus file. i want to complete schematic diagram. thank you
17 Dec 2017: 16:24 PM
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