Tag Families

A tag is a small archival data logger: it records to on-board memory and has no radio, so the data comes back only when the bird does. What separates one family from another is what it senses and how fast.

Three families have moved past prototype and are documented here. Others exist in the repositories at various stages and are not covered yet.

	BitTag	PresTag	IMUTag
Senses	Movement	Barometric pressure	Movement, rotation, magnetic field, pressure
Records	One activity bit per second, aggregated	Pressure and temperature at a set period	Acceleration, rotation, magnetic field, pressure, temperature
Answers	When was the animal active?	How high was it, and when did it climb or descend?	How did it move, wingbeat by wingbeat?
Sample rate	1 Hz, aggregated to 1 s – 5 min	Configurable period	100 – 1600 Hz
Deployment	Up to about a year	Set by the sample period	Hours of continuous recording; months armed and waiting
Processor	STM32L432KC	STM32L432KC	STM32U375

The trade running through that table is between resolution and endurance. A BitTag spends one bit per second and lasts a season; an IMUTag resolves individual wingbeats and fills its flash in a day. Choosing a family is mostly choosing where on that line a question sits.

All three are configured, armed and downloaded with the same tools, and all three produce data in the same formats. Those are documented once, in the software documentation, rather than per family.