#Arduino Garagedoor Unlocker

• Built using Arduino Pro Mini 5v
• You must initialize the Arduino's EEPROM with an initial passcode by uploading and running the eeprom_init.ino code before uploading this file.
• The servo connects to the door lock/unlock mechanism with a 4-bar linkage. A solenoid could be used as an alternative but would require an external power source as this cannot be provided by the Arduino.
• To activate the servo and unlock the door, enter the 4 digit code followed by # key.
• Servo rotates moving linkage and the lock/unlock mechanism, unlocking door.
• Door relocks after defined timeout.
• Pushbutton located inside door unlocks door immediately without requiring code entry.
• During unlock, enter new 4 digit code followed by * key to change passcode stored in EEPROM.
• The Arduino enters low power mode after timeout. Interrupts set on keypad and inside button wake device from low power.

Attributions

• Grallator - EEPROM, keypad input handling - grallator.wordpress.com
• Nick Gammon - Low power and wake with keypad - www.gammon.com.au
• madcoffee - Low power info & disabling power LED - www.home-automation-community.com

Schematic