The GPS module is OK. We reach GPS fix relative fast Fix Type "3D position", later it switches to "DGPS/SBAS aided 3D position" which is the best you can get without RTK capability.
The backup battery on the GPS module as reason of problems is a myth. The backup battery is only for faster GPS fix, not for better one.
No, I think, the GPS support is switched off by intention. Can you please double-check GPS setting in ST16?
In a relative early phase the parameter EKF2_AID_MASK is set to 0x20. That means, GPS is not part of the calculation. All following symptoms are related to this (no home position, GUIDED_ENABLED in MAVmode, reject Angle mode and so on).
In case Angle Mode is allowed, the parameter EKF2_AID_MASK is set 0x21=0010 0001 (bit 0 means use GPS).
dev.px4.io
I have compared two flights:
- With Angle mode: 00410, related sensor files 00356+357
- Angle Mode denied: 00468, related Sensor file 00410.
The following parameter setting are shown in the Sensor file 00356:
1504 00:01:07 COM_HOME_SET : Type: 6, Index: 134, Count: 802, Value: 0
1505 00:01:07 RTL_RETURN_ALT : Type: 9, Index: 610, Count: 802, Value: 35
1506 00:01:07 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 120
1507 00:01:07 RC_TESTPILOT : Type: 6, Index: 604, Count: 802, Value: 0
1508 00:01:07
EKF2_AID_MASK : Type: 6, Index: 165, Count: 802, Value: $21=0010 0001
1510 00:01:07 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
1515 00:01:07 COM_HOME_SET : Type: 6, Index: 134, Count: 802, Value: 0
1517 00:01:07 RTL_RETURN_ALT : Type: 9, Index: 610, Count: 802, Value: 35
1518 00:01:07 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 120
1519 00:01:07 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
1520 00:01:07 RC_TESTPILOT : Type: 6, Index: 604, Count: 802, Value: 0
1524 00:01:07
EKF2_AID_MASK : Type: 6, Index: 165, Count: 802, Value: $21=0010 0001
1533 00:01:07 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
And in contrast in Sensor file 00410:
1792 00:01:10 COM_HOME_SET : Type: 6, Index: 134, Count: 802, Value: 0
1793 00:01:10 RTL_RETURN_ALT : Type: 9, Index: 610, Count: 802, Value: 20
1794 00:01:10 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 120
1795 00:01:10 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
1796 00:01:10
EKF2_AID_MASK : Type: 6, Index: 165, Count: 802, Value: $20=0010 0000
1797 00:01:10 RC_TESTPILOT : Type: 6, Index: 604, Count: 802, Value: 0
1800 00:01:10 RTL_RETURN_ALT : Type: 9, Index: 610, Count: 802, Value: 20
1802 00:01:10 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 120
1803 00:01:10 COM_HOME_SET : Type: 6, Index: 134, Count: 802, Value: 0
1804 00:01:10 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
1805 00:01:10 RC_TESTPILOT : Type: 6, Index: 604, Count: 802, Value: 0
1806 00:01:10
EKF2_AID_MASK : Type: 6, Index: 165, Count: 802, Value: $20=0010 0000
1815 00:01:10 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
2302 00:01:18 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 20
3915 00:01:44 COM_HOME_SET : Type: 6, Index: 134, Count: 802, Value: 0
3916 00:01:44 LNDMC_ALT_MAX : Type: 9, Index: 290, Count: 802, Value: 20
3917 00:01:44 RTL_RETURN_ALT : Type: 9, Index: 610, Count: 802, Value: 20
3918 00:01:44 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
3919 00:01:44 RC_TESTPILOT : Type: 6, Index: 604, Count: 802, Value: 0
3920 00:01:44
EKF2_AID_MASK : Type: 6, Index: 165, Count: 802, Value: $20=0010 0000
3925 00:01:44 COM_LED_MODE : Type: 6, Index: 136, Count: 802, Value: $01=0000 0001
Maybe a PX4 Autopilot expert can say more about the GPS handling.
However, my eyes are directed to the ST16...
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