This guide shows how to build a safe ESP32 smart relay (Shelly-style) for Home Assistant using ESPHome (optional MQTT). Includes correct wiring (low-voltage vs mains), relay module selection, GPIO “safe pins”, EMI/noise tips, and example ESPHome YAML for a reliable…
This guide shows how to connect a PMS5003 (PM2.5/PM10) particulate sensor to an ESP32 using UART, configure it in ESPHome, and display air-quality values in Home Assistant (optional MQTT). Includes wiring, safe GPIO choices, recommended update intervals, warm-up/duty cycling tips,…
Quick SummaryThis guide shows how to connect an INA219 or INA226 current/voltage sensor to an ESP32 over I²C, configure it in ESPHome, and monitor battery/solar voltage, current, power and energy in Home Assistant (optional MQTT). Includes wiring, address scanning, calibration…
This guide shows how to wire a DHT22/AM2302 to an ESP32, set it up in ESPHome, and get temperature + humidity into Home Assistant (with optional MQTT). It includes the correct pull-up resistor, safe GPIO choices, recommended update intervals, and…
Understanding the Adafruit_PCF8575 Button Example Microcontrollers never seem to have enough pins. That’s where the PCF8575 comes in: a simple I²C 16-bit GPIO expander that gives you 16 extra digital pins using only 2 wires (SDA/SCL). The Adafruit example you…
The BME280 is a tiny environmental sensor that measures: From pressure, you can also estimate altitude, which is exactly what the Adafruit example you posted does. In this guide we’ll: 1. What is the BME280? The Bosch BME280 is a…
This guide shows how to wire an ADS1115 to an ESP32, choose the right gain, and understand the Adafruit ADS1X15 example so you get accurate voltage readings. The ADS1115 (16-bit) and ADS1015 (12-bit) are very popular external ADC chips. They…
This guide explains: Most ESP32 projects are powered from USB adapters and run 24 battery-powered sensors, that approach kills the battery in a few hours. To build long-lasting wireless sensors (temperature, humidity, leak, motion, etc.) running on 18650 cells or…
Sensirion’s SHT-series sensors are considered the gold standard in temperature and humidity sensing.They are used in industrial HVAC, medical devices, consumer electronics, environmental monitoring, and high-accuracy IoT projects. This article compares all SHT sensors, highlighting accuracy, stability, power consumption, differences,…
Bosch Sensortec is the leader in environmental sensing for IoT, and their BMP/BME sensors are used everywhere—from drones and weather stations to air-quality monitors and smart-home automation.Although many modules look identical, each generation offers different capabilities, accuracy improvements, and target…