This project enables real-time distance measurement using an ultrasonic sensor (HC-SR04) and displays the measured distance on a webpage. The ESP32 microcontroller reads the data from the ultrasonic ...

so , just connect the 4pin wire to it of ultrasonic sensor and other end will be free as its ultrasonic sensor 1. Define Pins for Trigger and Echo #define TRIG_PIN 8 // Define the Trigger pin #define ...