Hello friends! Today we will connect a real HC-SR04 ultrasonic sensor to an Arduino Uno and display distance on the Serial Monitor. Our earlier Proteus library tutorial introduced the simulated sensor, and the simulation examples explored different input conditions. This article moves to the four-pin physical module and the practical details of a measurement. Libraries HC-SR04 Simulation Libraries Latest library: Ultrasonic Sensor Library for Proteus V2.0 (October 2026): HC-SR04 with real TRIG and ECHO timing, Simple and Advance devices, test tools and an Arduino demo Other distance and motion sensors: JSN-SR04T · Sharp IR · TF-Luna LiDAR · VL53L0X · PIR HC-SR501 · RCWL-0516 · IR Obstacle FC-51 Helping Tools Serial Monitor Advance : a serial terminal window for the UART of your board Seria ...