Controlling a DC fan using PWM (Pulse Width Modulation) is an easy and cost-effective way to cool network cabinets, 3D printer enclosures, AV racks, routers, amplifiers, or any electronics that require temperature-activated airflow. This guide explains how to use an…
A reed switch is one of the simplest and most reliable ways to detect when a door or window opens. When combined with an ESP32, it becomes a fast, local, battery-free, and cloud-free door sensor that integrates perfectly with Home…
Monitoring indoor CO₂ levels is one of the most effective ways to track air quality, improve ventilation, and maintain a healthy indoor environment.The SCD30 and SCD41 are two of the best consumer-grade CO₂ sensors, offering accurate measurements and excellent long-term…
Bluetooth Low Energy (BLE) sensors such as the Xiaomi Mi Temperature, Inkbird, Switchbot, and many others are extremely popular for Home Assistant users.However, Bluetooth range is limited, and placing Home Assistant in a central location may not always be possible.…
I²C is one of the easiest ways to send data between microcontrollers. ESP32 and ESP8266 both support hardware I²C, and you can connect them directly using just two wires: SDA and SCL and common GND. This guide shows a complete…
ESP-NOW is a fast, connectionless communication protocol developed by Espressif. It allows ESP32 boards to exchange small packets (up to 250 bytes) with extremely low latency and very little overhead — perfect for sensors, dashboards, wireless controllers, and battery-powered devices.…
(Universal method — works with any ESP8266 board) ESP-NOW is one of the fastest and most reliable ways to send data wirelessly between ESP32/ESP8266 devices.Unlike Wi-Fi or MQTT, it requires no router, no pairing, and has almost zero latency (1–3…
Passive Infrared (PIR) motion sensors are one of the simplest and most effective ways to detect motion in a room. Combined with an ESP32, they provide extremely fast, local, cloud-free motion detection that integrates perfectly with Home Assistant. This guide…
The DS18B20 is one of the most robust and accurate digital temperature sensors for: It uses a 1-Wire protocol, allowing multiple sensors on the same wire, making it perfect for home automation. This guide includes two methods: 1. Parts Required…
The SHT45 is currently one of the most accurate temperature and humidity sensors available.It offers laboratory-grade precision, ultra-low power consumption, and very stable measurements. This guide shows you how to connect an ESP32 + SHT45 to Home Assistant using two…
Real-time energy monitoring is one of the most valuable additions to a smart home. The PZEM-004T module provides accurate measurements of: When combined with an ESP32, it offers a powerful, inexpensive way to send energy data directly into Home Assistant.…
ESP32 microcontrollers include multiple hardware timers that can trigger interrupts with microsecond precision. This makes them perfect for generating pulses, reading sensors, simulating RPM or speed signals, or scheduling tasks without blocking the loop(). In this article, we walk through…
The BME280 is one of the easiest sensors to integrate into Home Assistant for live temperature, humidity, and pressure monitoring. In this guide, we show you how to install the sensor, flash the ESP32, configure MQTT, and view the readings…
A simple example of sending multiple integers from one board to another The I2C (Inter-Integrated Circuit) bus allows two wires—SDA and SCL—to connect multiple devices.Each device can act as a master, slave, or both. In most projects, one board sends…
I2C is one of the simplest ways to connect multiple sensors and peripherals to your ESP32 using only two wires (SDA and SCL). When debugging a new project, the first thing you should do is scan the I2C bus and…