Signals

A signal is an object you hold, not a double you fetch:

RotemSignal<Double> yaw = imu.getYaw();

yaw.value();                   // 37.4
yaw.units();                   // "deg"
yaw.isValid();                 // false if the read failed
yaw.status();                  // why, if it did
yaw.deviceTimestampSeconds();  // when the device sampled it
yaw.ageSeconds(now);           // how old it is
yaw.isStale(now, 0.25);        // older than 250 ms, or invalid

A bare double has already thrown away everything you need to judge whether the number is worth acting on. By the time a heading reaches robot code it has crossed a bus that can drop frames, and the difference between “37.4 degrees, sampled 3 ms ago” and “37.4 degrees, sampled two seconds ago before the connector fell out” is the difference between working odometry and a robot driving into a wall with total confidence.

Two timestamps

Method	Meaning	Use it for
`deviceTimestampSeconds()`	when the device sampled the sensor	pose estimation
`receivedTimestampSeconds()`	when the frame reached this robot	judging staleness

Update frequency

Every status frame has an individually configurable rate, including zero to disable it:

imu.setUpdateFrequency(SapphifyProtocol.Api.STATUS_ORIENTATION, 250);

Defaults are chosen to be safe on a shared 1 Mbps bus carrying a full robot’s worth of devices. Raise orientation if you are running pose estimation at 250–500 Hz. On a CAN FD bus, prefer the composite frame, which packs the full estimator state into one large frame — the practical limit on Systemcore is frames per second, not bits per second, because its CAN interfaces share SPI controllers.