Box Controller

JSON: /api/status · history: /api/temperature/history

JSON: /api/log

The relay turns on at target − hysteresis/2 and off at target + hysteresis/2. JSON: /api/thermostat

A trigger switches the relay on and starts the countdown; a new trigger while it runs restarts the countdown. The input uses the chip's internal pull-up/-down, so a plain switch or open-collector output to GND (or 3.3 V) is enough. JSON: /api/timer

Changes apply immediately and are kept across reboots (outputs come back at their last level). Inputs without pull-up float when nothing drives them — wire a resistor or use the pull-up option. The timer's trigger input is locked here while the timer is on. Most opto-isolated relay boards are active low; changing the polarity keeps the relay's on/off state. Pins are 3.3 V only. JSON: /api/gpio

Sensors are found by themselves (plug in, wait a few seconds) and published to Home Assistant once seen. BMP280 temperature and pressure and AHT20 temperature and humidity can be logged (Logging page). Use 3.3 V modules or modules with their own regulator. JSON: /api/i2c

A device shows up here when the box receives an ESP-NOW frame from it – broadcast (to FF:FF:FF:FF:FF:FF) or sent to this box's MAC. Senders must use the Wi-Fi channel shown above (the router decides it). JSON: /api/espnow

Put the device in pairing mode (new or factory-reset devices usually are for a while after power-up) and keep it within a few metres of the box: pairing uses Bluetooth. The setup code is the QR code or the 11-digit number on the device or in its box. A device that belongs to another app (IKEA Home smart, Apple, Google, Home Assistant) can be added too: turn on pairing mode / "share" for it there and use the code that app shows. Thread devices join the box's own Thread network. JSON: /api/matter

With MQTT discovery the box shows up in Home Assistant by itself (Settings → Devices & services → MQTT): temperature, both relays, the thermostat, the timer and every ESP-NOW device the box hears. Leave the broker address empty to find the broker on the LAN via mDNS (an _mqtt._tcp service, e.g. Mosquitto announced by Avahi); the port then comes from the announcement. Leave the password empty to keep the saved one. The password is stored on the box in plain text. JSON: /api/mqtt

Gives each box on the network its own address, Home Assistant device name and setup hotspot. A new name takes effect immediately; your router may show the new hostname only after the box's next DHCP renewal. JSON: /api/settings

The check downloads ; the box sends nothing but the request. New firmware is installed over USB from the download page. JSON: /api/update