The intent of our final project was to create a keypad lock using a 12-key membrane keyboard and the XMEGA-A3BU board that would trigger a stepper motor to open a mechanical lock. We ran into a problem early on that forced us to change course slightly. The EasyDriver for the stepper motor we were planning on using for our lock did not arrive in time so we decided to go with an alternate driver. This ended poorly for us as the alternate driver caught fire during initial testing, much like our hopes and dreams.
As an alternative, we printed messages to the LCD while also flashing the onboard LEDs to signal that the provided password was correct or incorrect. We also implemented a menu system through which the user can either set or try a password. Passwords can be 10 digits or less, and are hashed upon entry for added security. If the user attempts to try a password before one has been set, an error message is displayed and the user is returned to the main menu.