Security Entrance System

Overview:
Our security system is a stand alone device that allows access to registered users identified by their magnetic cards.(For this project, “access” is represented by a lit LED, showing how the system could be used to control an external locking mechanism.)The system includes features such as:

• Multiple accounts, including Administrator accounts (which can create, modify, or delete the other accounts). The account information is stored in non-volatile EEPROM memory, so that it is maintained even if the system is reset.
• A “lock down” of the system when someone tries to gain access by repeatedly swiping incorrect cards.
• A 20×4 LCD display to give the user feedback on the current state (such as “Access allowed.” or “try swiping the card the other way.”) and to prompt administrators for commands. All messages printed to the LCD are simultaneously transmitted to an RS232 port, so that all activity can be logged by a PC.

Design:
There are three basic modes of operation:
Normal Mode:
When a card is swiped, the system compares the number on the card to the list of numbers in the EEPROM database compare the number in its database. If a match is found, an the EEPROM lookup reveals that the account has not been disabled, the system prints a friendly message and lights the “access” LED for 4 seconds, representing the time that the door would be unlocked.

If the account number belongs to a system administrator number, then the administrator is prompted to enter a new mode via the keypad.
If more than three invalid attempts are made in a row, (i.e. presumably by a person who is not authorized for entrance) then an LED representing an alarm is activated, and the system goes into a lockdown mode.
Lockdown Mode:
While the system is in Lockdown mode, only administrators will be recognized. In addition to the ability to lock down after several failed attempts, this feature provides a convenient way for administrators to temporarily disable all non-administrator access, without having to modify each account individually,

For more detail: Security Entrance System