This repo is a familiarisation exercise with GitHub, and its version control, planning and documentation tools.

The project itself is code I wrote with extensive help from ChatGPT a while ago. It uses MicroPython to control a Raspberry Pi Pico which has a DHT20 sensor and a simple light dependent resistor (LDR) circuit attached. The system takes readings from the sensors every minute, and submits them to an MQTT broker. Home Assistant is subscribed to the appropriate topics and can parse the data for logical operations (turn a light on if it's dark etc.)

Each sensor platform has a BOM of about £20 including its Pico, USB cable, breadboard, header pins, sensors and jumper wires. They can be used to control a smart home, and are easily modified to add or replace sensor types. Using MQTT, they are not dependent on any proprietary smart home system such as Ikea Trådfri or Philips Hue, but using Home Assistant can push information out to Apple Home or Google equivalents.

The code was previously kept in a local Bookstack instance, but this has no version control etc. I intend to keep the code here, improve on it, and document its development, functionality and improvement.

The system runs well- months at a time when the MQTT broker is constantly available. When the MQTT broker is unavailable however (due to a reboot or the WLAN dropping), the system fails to recover from the interruption and remains offline pending a restart. This should be easy to investigate and fix, but it's the documentation of this process that is important.