the hackernews firmware for nRF51 chips that’s coincidentally compatible with the FindMy (AirTag) ecosystem.
You might perhaps presumably presumably furthermore examine this mission right here.
It sends out advertisement keys outlined in keys.h, rotating keys every hour.
Additionally, an input pin can even be outlined. At any time when that input pin is prompted, the plan byte increments by one.
The principle two bits of the plan byte maintain battery facts, the loads of six bits maintain the counter in my code.
I employ this for my Mailbox-sensor.
There’s a vibraion sensor linked to the board, and whener the Mailbox is opened the vibration sensor triggers, which
makes the chip send out a assorted plan byte.
That plan byte, traveling via the FindMy community and OpenHaystack, reaches my smarthome and I receive a notification.