Using ATMEL AVR combination lock

Code lock based on ATMEL AVR

The CodeLock AVR electronic combination lock is implemented using an Atmel AVR microcontroller, either the AT90S2313 or ATtiny2313. The hexadecimal code program is 2 kB in length. The user code consists of 1 to 4 digits. If you purchase a chip, the user code consists of 1 to 8 digits. If the codes are entered in the correct order, the relay and electric lock striker (in the door) will open for 1 second and then close again. The user code can be changed via a 3x4 matrix keypad. CodeLock keypads can be purchased at your local electronics store. The initial user code (1234) is set via a jumper. The jumper must be inserted before the voltage (12V) connection. The jumper must be removed after two beeps (5 to 15 seconds).