Espressif’s ESP32 family has exploded with variants, but for most makers and IoT projects the real question is simple: Should I use the classic ESP32, or the newer ESP32-S3? Both chips are dual-core Wi-Fi + Bluetooth SoCs, both are cheap,…
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…
Understanding the Adafruit ADS1X15 Example The ADS1115 (16-bit) and ADS1015 (12-bit) are very popular external ADC chips. They talk over I²C, give you 4 analog inputs, and include a programmable gain amplifier (PGA) so you can measure both tiny and…
If you want one “single source of truth” for indoor air quality, the most useful combo is: With an ESP32 you can build a compact air quality station that reports to Home Assistant and gives you: This guide shows wiring…
Wi-Fi is great indoors, but it often fails for: LoRa solves this problem: it’s long-range, low-power, and ideal for small sensor payloads. This architecture works extremely well with Home Assistant: LoRa sensor node (remote) → LoRa gateway (near Wi-Fi) →…
A huge amount of serious home energy hardware speaks Modbus RTU over RS-485: With one ESP32 and a cheap MAX485 (RS-485) transceiver, you can build a gateway that: This guide covers: 1. Modbus RTU & RS-485 in 2 minutes 2.…
If you’ve ever forgotten wet laundry in the washing machine for 3 hours, you already understand the value of this automation. Laundry machines and dryers have a very distinct power signature: By monitoring power, Home Assistant can reliably detect: This…
A classic doorbell can be upgraded into a smart doorbell with just: With Home Assistant you can: This guide covers: 1. Hardware Overview Base setup (no camera): Optional add-on: ⚠️ If your doorbell is powered by mains voltage, only work…
A lot of garage doors and sliding gates already have a simple “push-button” input that: With an ESP32, a small relay, and a reed switch you can turn that into a fully integrated Home Assistant device: This guide focuses on:…