Electronic lock 4 digits code. Digits are stored in the EEPROM. To change code press pushbutton once and enter 4 digits. The relay operates for 2 seconds to unlock. B4R code uses rEEPROM lib and rWIRE lib.
The keypad is matrix 3x4, the Oled is 0.96", 128x64, SSD1306 driver, I2C. The code lock...