Sensors and Modules for Arduino, Pi and ESP32

This hub covers the parts that let a microcontroller sense and act on the world: environmental and motion sensors, displays, relays and the breakout modules that tie a build together. Each guide explains how a component works, how to wire it safely to an Arduino, Raspberry Pi or ESP32, and how to get reliable results in code. It is written for hobbyists, students and robot builders who want circuits that work the first time.

What you'll find here

Sensor wiring guides

Clear connection walkthroughs for popular parts such as the DHT22, HC-SR04 ultrasonic rangefinder and BME280, with notes on pull-up resistors, voltage levels and sample code.

Displays and screens

Practical setup for character LCDs, SSD1306 OLEDs and small TFT panels, covering I2C and SPI wiring along with the libraries that drive them.

Relays and power control

How to switch lamps, pumps and motors using relay modules, MOSFETs and motor drivers without overloading a 3.3V board or creating a shock hazard.

Comparisons and troubleshooting

Side-by-side looks at similar modules, plus fixes for common problems like noisy readings, I2C address conflicts, logic level mismatches and loose jumper wires.

2 guides in this section