Here 4 compass issue

Here GPS
1

Hello everyone,

we are currently experiencing a strange issue with the HERE4 GPS/compass modules after updating to the latest firmware.

Setup:

ArduPilot

2× HERE4 modules

Used with moving baseline

Problem: After installing the latest firmware version on both HERE4 units, ArduPilot only detects two compasses coming from a single module, instead of detecting one compass per HERE4.

So instead of seeing:

HERE4 #1 → 1 compass

HERE4 #2 → 1 compass

we see:

One HERE4 providing 2 compasses

The second HERE4 does not appear correctly

Important observation: If one HERE4 is running the latest firmware and the other one an older firmware version, everything works normally and both modules appear correctly as two separate compasses.

As soon as both HERE4 modules are updated to the same current firmware, the issue appears again.

Has anyone experienced this behavior before or knows if this is a known firmware bug related to moving baseline or compass IDs?

Any help or confirmation would be greatly appreciated.

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Thanks in advance!

2

So, I have now found out that the error occurs starting with version 1.15.4. In version 1.15.3, each GPS has one compass, and no two compasses are displayed on a single module.

3

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ok what does the point “send both AKM and RM3100 compass data over CAN” means?