Library Reference

Read temperature and humidity from DHT11, DHT21, and DHT22 sensors.

Common sensor data abstraction layer required by most Adafruit sensor libraries.

Driver for the BME280 temperature, humidity, and barometric pressure sensor over I2C/SPI.

Fast, accurate distance readings from HC-SR04 and similar ultrasonic sensors.

Driver for SSD1306-based monochrome OLED displays (128x64, 128x32) over I2C/SPI.

Drive 16x2 / 20x4 character LCDs through a PCF8574 I2C backpack with just 2 wires.

Built-in library for controlling standard hobby servo motors with precise pulse timing.

Servo control for ESP32 boards using the LEDC PWM peripheral (the standard Servo library doesn't support ESP32).

Lightweight MQTT client for publishing and subscribing to topics over Wi-Fi or Ethernet.

Parse and generate JSON efficiently on memory-constrained microcontrollers.

Asynchronous HTTP and WebSocket server for ESP32/ESP8266 — handle requests without blocking the main loop.

Read and set time from DS1307, DS3231, and PCF8523 real-time clock modules.

Read and write files on SD/microSD cards using the standard FAT filesystem.

Parse NMEA sentences from GPS modules into easy-to-use latitude, longitude, speed, and time data.

Send and receive infrared remote control signals (NEC, Sony, RC5, and more).

Send and receive LoRa packets with SX1276/SX1278-based modules (e.g. RFM95, Ra-02).

Low-level driver for the 1-Wire bus protocol used by DS18B20 temperature sensors and similar devices.

High-level driver for DS18B20 waterproof digital temperature sensors, built on top of OneWire.

Control WS2812/WS2812B/NeoPixel addressable RGB LED strips and matrices.

High-performance library for controlling addressable LED strips with advanced color and animation effects.

Built-in I2C (TWI) communication library — the foundation almost every I2C sensor library is built on.