I have always been interested to make an electronic security system with a LCD display and numeric keypad controlled by a Microchip PIC microcontroller. This project took me whole two days to both research and implement the circuits on the prototype boards. The project could be further improved to integrate with an actuator which can manipulate the door lock & etc. In case you want to ask where I purchased most of my electronic components, check out http://www.futurlec.com or http://www.rssingapore.com.

You may view or download the article for this project here:
http:/king.iplussoft.com/pic_keypad_lcd.pdf

Download the assembly source file (.asm):
http:/king.iplussoft.com/asm_pic_lcdkeypad.zip

A brief video demonstration of the project:
http://www.youtube.com/watch?v=dMFbWLK5kGE