Triggering an action on a Pi when the button is pressed

HID on Pi 3

Strange. Personally I haven't had it working, but I have definitely done it on Desktop linux so I wonder what's up.

Could it be that something like EspruinoHub is effectively 'claiming' the BLE interface and breaking things? IIRC for Bleno to work you basically have to disable bluetoothd, and I guess it's bluetoothd that handles all the HID stuff.

where is the Bluetooth object documented?

Hmm. Looks like it isn't. I'll fix that, but yes - it's basically just a 'Serial' object

Glad you got it working with Node.js in the end. I will eventually add something that'll get lower power consumption on the Puck when it's connected.

Personally I'd say to use NRF.setAdvertising and work on received advertising data. EspruinoHub should pick that up without a connection (or it's pretty easy to do with Noble directly or even hcitool), and it's not actually using substantially more power than the usual advertising it does by default.