Trust each sensor

Set home on starts at First arm. The hint says that choice keeps home after an accidental mid-air disarm. Never leaves the home you already have. Every arm sets home again each time you arm. Zero altitude on uses the same three choices and also starts at First arm. That second field has no hint on the card.

GPS altitude without barometer starts off. The hint says turning it on allows altitude hold and return to home on a board that has no barometer. Use GPS velocity starts on. Off works speed out from positions instead. The hint says to try off if the GPS lags, and that it must be off with the Pedestrian GPS model.

Position usable within starts at 10 m. The step is 0.5 m and the value is shown to one decimal. The hint says the estimated error must fall below this before navigation is allowed. Barometer uncertainty starts at 1 m, in steps of 0.1 m. Gravity calibration tolerance starts at 5 cm/s², from 0 to 255. Calibration at power-on waits until the error is below that.

The weight fields use two decimals and step by 0.05, except accelerometer drift, which uses three decimals and steps by 0.005. A higher weight trusts that sensor more. The footer says it reacts faster and passes on more of the sensor's noise.

Altitude from the barometer starts at 0.35, and altitude from GPS starts at 0.2. Climb rate from GPS starts at 0.1. Climb rate decay without a reference starts at 0.5. Those four run from 0 to 10. The decay hint says it is how fast climb rate fades when the barometer and GPS are both lost.

Rangefinder altitude weight starts at 3.5, and rangefinder climb rate starts at 6.1. Both run from 0 to 100. Position from GPS starts at 1, and speed from GPS starts at 2, both from 0 to 10. Speed decay without GPS starts at 0.5, and its hint says that is how fast speed fades when GPS is lost.

Optical flow position starts at 1, and optical flow speed starts at 2, both from 0 to 100. Accelerometer drift learning starts at 0.01, from 0 to 1. Leave the defaults alone unless a log shows one sensor fighting the others.

Accelerometer P and compass P start at 2000 and step by 100, from 0 to 65535. Accelerometer I and compass I start at 50 and step by 5, over the same range. The footer says these gains are stored times 10 000, so 2000 is 0.2. A higher P corrects drift faster from the accelerometer or the compass, and it lets vibration and acceleration tilt the horizon.

Accelerometer trust cut-off starts at 15 degrees per second, from 0 to 30. The hint says that is the rotation rate at which the accelerometer counts half. Fade width starts at 5 degrees per second, from 0 to 10, and the hint says the weight fades over that range either side.

The picture uses the demo pair, 15 and 5. Full trust holds up to 10 degrees per second. Half is at 15. From 20 the accelerometer is ignored. Between 10 and 20 the picture fades in a straight line, and the horizon leans only as that trust falls. That straight line is the picture, not a claim about the firmware's own curve.

GPS heading weight starts at 100 percent, from 0 to 500, in steps of 10. The hint says that with a compass, 0 is compass only and 100 counts the GPS course as much as the compass. Wind-correct GPS heading starts on, and only a plane, boat, rover or other platform shows that switch. A multirotor hides it.

Open Advanced nav and find Position estimator, then Attitude estimator. The block is there when the board has the baro altitude weight or the accelerometer P. The compass alignment itself is on the Compass tab. These gains are only how hard the compass pulls once it is aligned.

Chrome or Edge connects over USB or Bluetooth. Android adds Wi-Fi. iPhone uses Bluetooth or Wi-Fi and has no USB host. Save only when you are ready for the flight controller to reboot.