Total mastery over the pinout and functionality of the PCA9306 for conversion of logic levels from 5V to 3.3V. A step-by-step ...

RFID Module: Reads the UID from an RFID tag/card. If the UID matches the authorized UID, access is granted. Ensure the RFID tag ...

If your buzzer is active-HIGH, flip the code flag (see “Configuration”). If you discover your buzzer is 5V-only, power it at 5V and use a small NPN/MOSFET level driver for I/O (ask if you want a tiny ...