Cannot see external barometer data – NO SCALED_PRESSURE3 message

[EliotBR (Eliot)]

@EliotBR

ArduPilot handles this a little weirdly, by using RAW_PRESSURE as the data for the first barometer.

This was incorrect - I was mixing it up with RAW_IMU messages.

The actual problem here is a bug in ArduSub, which is being discussed here, with a fix in progress.