CAN bus digital airspeed sensor problems

I am getting a lot of “unhealthy” airspeed indications, and see this message repeatedly in my flight log:
CAN[113] IERR 0x800 240
Any idea what this means?
Also, despite that this is a digital airspeed sensor (Matek ASPD-DLVR using its CAN bus connector to a Matek H743 FC) it is indicating 14kph airspeed in still indoor air. I thought digital airspeed sensors did not need to be calibrated, no?
It gets adjusted in flight using GPS, and seems to work in general, but I don’t want sensor problems to prevent me from arming the plane.
Let me know how to debug this problem.

Hi @stevempotter

All air speed sensors need to be calibrated to remove the zero offset.
Here you will find a more detailed explanation how airspeed sensors work and why they need a calibration.

The main difference between a “digital” and an “analog” one is the way the sensor communicates with the flight controller.

Hope this helps.

Thanks, I have now calibrated it to remove the offset.
But what about that error,
CAN[113] IERR 0x800 240
What does this mean? Is there a place to look up such errors?
How can I get rid of that and the unhealthy airspeed messages?

Did you ever solve this Steve? I have one of these and I’m seeing the same error.

I think I solved it, though I have not looked at the flight logs to be sure. There was some setting in Arduplane that calibrated the airspeed sensor when I flew in circles for 5 minutes. This calibration gets saved, so now the airspeed on the bench is close to zero. The most important thing is to make sure you see the airspeed indicator in Mission Planner go up when you blow on the pitot tube. Then you know it is working and connected. Then calibrate as per the instructions linked above.

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Thanks Steve - I updated the firmware on the airspeed sensor using Mission Planner DroneCAN/UAVCAN. I turned on SLCAN by setting CAN_SLCAN_CPORT = 1. Then I downloaded the firmware and uploaded it using the Menu → Update option.

I now have readings “on the bench” (e.g. if I blow), so I’ll try calibrating it in the air as you suggest.