WeatherFlowHK Bridge

Very basic HomeKit bridge for WeatherFlow Tempest Weather Station.

About

Uses an ESP32 based microcontroller to listen to the UDP packets sent from a Tempest bridge and relays them out as HomeKit HAP Notifications. No internet connection required and everything stays local.

Directions

1). Install with Arduino IDE

Open the Arduino sketch WeatherFlowHK.ino in the Arduino IDE
Install both the HomeSpan and ArduinoJson libraries

Sketch > Include Libraries > Manage Libraries
Follow the directions here to install the various ESP32 boards or install whatever is relevant to your specific board and select the board you are using from

Tools > Board > ESP32 Arduino > Your Board
Upload the sketch to the board with Sketch > Upload or click the little arrow pointing right in the top left corner of the window

2). Configuring the device for HomeKit

Open the Serial Monitor by clicking the magnifying glass in the top right of the window or Tools > Serial Monitor
Change the line ending to Newline and the baud to 115200 (bottom right of the Serial Monitor)
Type "W" into the serial input and press Send or press the enter key on your keyboard then follow the prompts

3). Connect to HomeKit

Add the device like you would any other accessory by using your camera to scan the code above or typing 466-37-726 in manually

**Optional: Set your own code within the Serial Monitor by typing "S"**

Functionality

There are currently no services in the HomeKit specification that display anything other than temperature, humidity, and light levels. Hopefully that will eventually change, but until then rain, wind, and lightning are simulated buttons to trigger actions. The thresholds are currently hardcoded but will eventually be adjustable via a small webpage served from the device.

Wind

Action	Trigger
Single Press	Wind over 10m/s (~22mph)
Double Press	Nothing
Long Press	Nothing

Lightning

Action	Trigger
Single Press	Every event
Double Press	Only if last SENT event was more than 5 seconds ago
Long Press	Only if last SENT event was more than 10 seconds ago

Note: this is only the last by the last event announced to HomeKit. This will be eventually changed to last received event.

Rain

Action	Trigger
Single Press	Every event
Double Press	Nothing
Long Press	Nothing

Future

Add save most resent values to NVS for better numbers upon reboot
Add webserver for adjusting event thresholds
Display more info via sensor names e.g. "Wind: 1.4m/s"
Support for Air and Sky
Add optional BLE subscription to hub

Dependencies

Uses the wonderful HomeSpan library for HomeKit functionality and ArduinoJSON for parsing the UDP datagrams.