Altitude display - ShikOfTheRa/scarab-osd GitHub Wiki

Definition of altitude in context of MWOSD:

It is always height above launch / arming point.

Display options

There are two altitude display options available in the GUI configurator – "altitude" and "GPS altitude".

Display icons

There are 3 alt indicators - "AGL","ALT:" and "ALT::"

"ALT:" - This is the altitude from prime source

"ALT::" - This is GPS altitude

"AGL:" - This is displayed when any altitude displayed is below the threshold set by “High resolution altitude display cutoff”. The default value for this is zero. Typically this is used when the aircraft has LIDAR or an FC that can send altitude data with accuracy of less than 1 meter. Recommend using only for iNAV copter users and Ardupilot PX4 users with barometric data. AGL is displayed with extra digit of precision

Prime source of altitude:

Ardupilot/PX4 – always GPS unless using custom install with LIDAR, depth sensor.

Fixed Wing – always GPS.

Copter – usually barometric altitude.