Display the relative time (15 seconds ago, 2 minutes ago) since the last sensor reading at UUID f0cd2004-95da-4f4b-9ac8-aa55d312af0c.

So here's an interesting new problem. Right now in Chrome Canary, if I run the example and pair with my Aranet4, I get a DOMException: GATT operation not permitted. error. What makes it interesting, is that if I comment out the CO2 characteristic,
f0cd3001-95da-4f4b-9ac8-aa55d312af0c, I have no such problem.

The way I understand Chrome, this means, that for some reason the Read bit for that characteristic isn't set?!?

https://chromium.googlesource.com/chromium/src/+/346fea951d1cec1bd49d4afca19ec9fc0a6b8124/device/bluetooth/bluetooth_remote_gatt_service_android.cc#68

https://chromium.googlesource.com/chromium/blink/+/refs/heads/main/Source/modules/bluetooth/BluetoothError.cpp#51

https://github.com/chromium/chromium/blob/master/third_party/blink/renderer/modules/bluetooth/bluetooth_error.cc#L169

What the heck?

I can't open my own aranet4 device, and neither can a few other people. We're hitting this error:

NotSupportedError: GATT operation failed for unknown reason.

Any idea what's going on? I want to pair with aranet devices in my own app, but I'd like to experiment with it in your sample first 👍

ThankYou for the great pilot! I wonder -history reading - is it something that is accesible over the webBTapi, just need a time/hands? Or it's not exposed/accessible?

In Aranet4 FW >= v1.2.0 the advertised service UUID and the service UUID containing Aranet4 measurements has been changed:

• Prior to FW v1.2.0 the service UUID is f0cd1400-95da-4f4b-9ac8-aa55d312af0c.
• With FW v1.2.0 and newer the service UUID is 0000FCE0-0000-1000-8000-00805f9b34fb.

Advertised service uses Bluetooth assigned 16bit UUID = 0xFCE0.
For Bluetooth assigned UUIDs base is 0000xxxx-0000-1000-8000-00805F9B34FB.
So 16bit UUID 0xFCE0 in 128bit format looks like 0000FCE0-0000-1000-8000-00805F9B34FB.
Service also uses 16bit UUID = 0xFCE0 (0000FCE0-0000-1000-8000-00805F9B34FB).
All custom Characteristics use the same previously used custom 128bit UUIDs f0cdXXXX-95da-4f4b-9ac8-aa55d312af0c.

See:

• https://github.com/h4/lywsd02
• https://github.com/hobbypunk90/mithermometer
• https://github.com/sullin/hyg