tag: homeassistant

My wife asked for a sensor that would inform her of the next bus here in Ottawa. Turns out they have an actual API! Someone had tried this on the forums before but said the API had changed1. ...

I’m pretty happy with my SensorPush outdoor temperature/humidity/pressure sensor. It’s not cheap but it is calibrated to work in a Canadian winter (most of it, at least). Their BLE adverts are automatically detected by HomeAssistant and decoded. Sometimes it appears to have a bit of a nap, adverts stop arriving (and I’ve checked with other BLE receivers) until the Android app wakes it up, probably the direct Bluetooth connection is all it wants. Also, the battery voltage doesn’t appear to be broadcast. SensorPush do actually publish an API but they only show the GATT characteristics that require active scanning. Also my readings don’t agree with their statement that I can read battery temperature. The Android app happily returns 20.9C (which seems high!), raw values seem to float around 0xffff. So, rather than try to get an ESP32 to lock up its active connection, draining the battery to see how quickly the battery is draining, I’m going for something more intermittent. ...

A nerd friend bought me a LILYGO E-paper display1, in the exact hope that I’d end up going down the rabbit hole of Smart Things. I have gone down this bloody rabbit hole. I’ve always been a sucker for data, and I aspire to heating my home more efficiently by measuring temperatures round the house and seeing how they change as I change demand. This is not a place of honour. It’s a place of a lot of YAML and black magic. It’s pretty cool when it works though: The board is a micro with Wi-Fi and a big-enough E-Paper Display (EPD) I can reconfigure it via context-aware text editor in the browser Push updates (also from the browser) Do some reasonably complex data processing and image/text rastering on the micro itself Control it from either a self-hosted server on the micro or from Home Assistant ...