OSDK 3.3 - Telemetry sample crashes with "Bus error"

[hhackbarth]

Testing the telemetry sample on a RasPi Zero.

Everything seems to work fine until the loop starts. When a value is retrieved with
vehicle->subscribe->getValue<TOPIC...>()
the program crashes after reporting "Bus error" to the console.

Clean termination with removePackage is not carried out. If the program is started a second time, after initialization it immediately reports "ERROR/1 @ extractOnePackage, L364: Package does not have a valid DataBuffer".

I tried to reduce the amount of data by only subscribing to package 0 and 1 with reduced frequency. This did not help. Also reducing the output frequencies in the SDK configuration did not help.

[rohitsantdji]

The general opinion on various forums (example 1, example 2) is that variants of the Raspberry Pi do not like unaligned memory access (packed structs), which are used quite frequently in the DJI OSDK.

You could try going in to dji_telemetry.hpp and commenting out the #pragma packing, though we have not tested the SDK using this configuration so it is unexplored territory.

[hhackbarth]

Thank you for your quick comment!

I tested it with commenting out the #pragma packing in dji_telemetry.hpp:
It does'nt crash anymore but now it shows weird figures for the latitude, longitude and altitude.

Looks like the telemetry cannot be used on RasPi (tested with Pi Zero and Pi 2 B).