Where dose the diff_pressure valuse come from in the HIGHRES_IMU message

Hello all,
I am trying to read the diff_pressure in the HIGHRES_IMU mavlink message. I am running px4 Hardware in the loop plane with xplane 10. When I read the diff_pressure values all I get is 0. This leads me to my question. Could it be that xplane 10 dose not publish this value?

I have no experience with xplane but could be I guess that it just doesn’t publish diff pres.

yea that’s what I am thinking to. I ended up grabbing the VFR_HUD airspeed.

thanks for the reply