I don't know the P3P well enough to know whether either the AC DAT has the detailed GPS data.
How many satellites for your home point to be updated? (Poll)
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I don't know the P3P well enough to know whether either the AC DAT has the detailed GPS data.
Interesting, but not a complete power up sequence - the aircraft has already powered up and acquired satellites and home point before the start of that log file. It does, however, show that the aircraft uses GPS positioning with a satellite count of 6, a NavHealth of 3 and a pDOP of around 3.
Yes there was actually 2 files for that time period, i was fooling with the flight mode switch and when I selected Fmode the props started to speed up so i quickly did a motor stop and restarted them, this is the data after that.
I'm not sure what you want us to look at. In FLY217.DAT I think what you'll see is that navHealth made it to 4 at one point. This will cause the home point to be set and a switch to GPS mode. The MC can get confused about when it should and shouldn't update a home point. Take a look at this incident. Seems that a home point gets recorded when navHealth makes it to 4. But, a subsequent lowering below 4 and then back to 4 won't cause the home point to be updated.
Mavic disconnected, and flew away.
In FLY218.DAT I don't see any of the switching to and from ATTI that you've described.
I think there would be something to be concerned about if this were a normal scenario where the P3P is powered up outside with plenty of satellites.
When i say switched to Atti, I mean that I'd lose the Green "Ready to fly GPS" in the app and the rear arm leds would switch to a slow flashing yellow. When I'd get 6 satelites back both the app and rear leds would switch back to green.
I suspect that the Green "Ready to fly GPS" indicator means that GPS will be used. Not quite the same as being in GPS mode.
Yes I understand that. My flight mode was set to P-GPS. And since I was indoors with the AC sitting on my coffee table GPS was kicking in and out. Tbh it was the first time I ever noticed it acquiring GPS inside, must have been in exactly the right spot. The only reason I had the AC powered up was to bring the battery down after my earlier 4 minute test flight at minus 31c. Had the props on and idling to keep the gimbal cool and drain the battery down to 60%. Then I noticed I was green in the app and on the AC and remembered this thread so I quickly took a pic of my tablet screen to prove 6 satelites can be enough for GPS to be active.
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I wonder if the change in the last 6 seconds was due to me shutting down the motors??
Yes.
2420.837 : 122866 [M. Stop]landing.exit_takeoff
2420.837 : 122866 Motor Start 3 Total 2420.88
2420.837 : 122866 CTRL reset all by motor stopped
2420.837 : 122866 [Ctrl<2>] REQ_RC_COMMAND ENGINE_START ctrl_engine_start
2420.857 : 122867 [Ctrl<1>] REQ_RC_NORMAL ATTI_HOLD ctrl_gps_atti
2426.298 : 123139 Battery power off
Ok here's the previous .dat file that will show the start up and home point recording data:
FLY217.DAT
At time 570 secs the home point is set for the first time. It seems to be coincident with navHealth reaching 4 for the first time. pDop and hDop both had been less that 2.0 for several secs prior.
and from the eventLog stream
569.958 : 29917 53.5892472 -113.4697171 640.54 First Home Point
569.958 : 29917 53.5892472 -113.4697171 640.54 Home Point
So it's possible that it's navHealth reaching 4 for he first time that enables the home point to be set.
You plotted the number of GPS satellites but neglected to include the GLONASS data - it had 3 of those, for a GNSS total of 8:
