Description: CodeLock AVR electronic combination lock is realised with Atmel AVR microcontroller AT90S2313 or ATtiny2313. Program in hex code is 2 kB long. User code is consisted of 1 to 4 digits. If you buy the chip than user code is consisted of 1 to 8 digits. If the code is entered in the correct sequence, then after 1 second the relay and the electric striker (in the door) switch on for 1 second and then switch off again. User code can be changed via 3x4 matrix keypad. More: Keypad for CodeLock can be bought at local electronic shop. Initial user code (1234) is set up with a jumper. The jumper must be inserted before the voltage (12V) connection. The jumper must be removed after 2 beeps (after 5 to 15 seconds). LCD display
The CodeLock system utilizes an Atmel AVR microcontroller, specifically the AT90S2313 or ATtiny2313, as the core processing unit. The microcontroller is programmed with a 2 kB hex code that manages the logic for user code entry and validation. The user code can consist of 1 to 4 digits by default, but if a specific chip variant is purchased, it can support user codes of up to 8 digits.
The system is designed to operate with a 12V power supply. An initial user code of "1234" is preset and can be configured through the use of a jumper. This jumper must be inserted prior to connecting the power supply to the circuit. Once the system is powered on, the jumper must be removed after the unit emits two beeps, which indicates the end of the setup period (5 to 15 seconds).
User interaction with the system is facilitated through a 3x4 matrix keypad, which allows for easy input of the user code. Upon successful entry of the correct code, the microcontroller triggers a relay that activates an electric striker mechanism installed in the door. This relay remains energized for 1 second to allow the door to unlock before automatically switching off.
An LCD display can be integrated into the system to provide user feedback, such as prompts for code entry or confirmation of successful unlock attempts. This feature enhances user experience by providing visual confirmation of actions taken.
The components required for assembling the CodeLock system include the microcontroller, a relay, an electric striker, a 3x4 matrix keypad, and an LCD display, along with necessary passive components for interfacing and circuit stability. The design emphasizes security and usability, making it suitable for various applications where controlled access is necessary.CodeLock AVR electronic combination lock is realised with Atmel AVR microcontroller AT90S2313 or ATtiny2313. Program in hex code is 2 kB long. User code is consisted of 1 to 4 digits. If you buy the chip than user code is consisted of 1 to 8 digits. If the code is entered in the correct sequence, then after 1 second the relay and the electric striker (in the door) switch on for 1 second and then switch off again.
User code can be changed via 3x4 matrix keypad. Keypad for CodeLock can be bought at local electronic shop. Initial user code (1234) is set up with a jumper. The jumper must be inserted before the voltage (12V) connection. The jumper must be removed after 2 beeps (after 5 to 15 seconds). LCD display
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