Real-time access control using RFID tags. Visual feedback with LEDs: Default LED stays ON to indicate system readiness. Green LED lights up for access granted. Red LED lights up for access denied.

Real-time access control using RFID tags. Visual feedback with LEDs: Default LED stays ON to indicate system readiness. Green LED lights up for access granted. Red LED lights up for access denied.

But there are really just the two speeds with the current programming. Inside the cool laser-cut box is an Arduino Uno and a 9V battery, plus a current-limiting resistor and the all-important buzzer.

Arduino has launched its next generation of UNO boards, introducing a 32-bit Renesas microcontroller and Espressif ESP32-S3 module, one-click cloud connectivity and plenty of I/O plus a 12×8 red LED ...