gavinj.net

A complete tutorial for bringing an Arduino UNO R4 WiFi into Home Assistant with ArduinoMqttClient, MQTT discovery, two onboard controls and two useful sensors.

My first three ESPHome projects turned a LILYGO T-Embed, a Nano ESP32 and a Waveshare reflective display into useful Home Assistant devices.

My cheap 12 V Starlink cable produced random reboots and Wi-Fi without Internet. A boost converter, a forgotten Anderson lead and some newfound soldering confidence finally gave the caravan a reliable setup.

I finished the second half of my oscilloscope basics lesson, broke out the Arduino UNO, chased a weird waveform, and learned why AC coupling is not what you want when probing a digital pin.

My new soldering iron arrived, the B-Sides Canberra Amulet of Entry finally lit up, and the FNIRSI DSO-TC4 helped me identify LEDs, capacitors, transistors, and the limits of cheap component testers.