For Project 3 we created a security system which consisted of an end user typing username and code into the keypad and a security guard accessing the system over RS232 serial cable using Window’s Hyperterm. For this project, use the the updated keyboard files from here. In the project code removing the #define EXTRA_CREDIT will make it the base 4-digit code system, otherwise it is a username/password system. The keypad page for this lab explains how to use it for typing letters.