Wrong NEO-MP8 RTK configuration [Solved 3.5 firmware needed]

I was able to make working a Drotek NEO-MP8 RTK system with Pixhawk and Mission Planner
I upgraded a month ago the NEO-MP8 firmware with Ublox latest version .
To make it work I had to disable the Mission Planner feature of autoconfig the GPS .

Now after some weeks i started to use it again and I notice a strange behavior of the NEO-MP8 system with Mission Planner

  1. If I do not let Mission Planner to configure the NEO-MP8 (Autoconfig =0)
  • I obtain a very high Hdop , from 2 to 1,3 and 13 - 14 sats
  • When I inject the RTK datas with MP the led on the rover starts to blink red but never becomes steady so I never reach the RTK fix even if the position of the drone at ground become more and more precise, guess I obtain only a floating fix.
  • In Mission Planner 3D Fix label is replaced by DGPS
  1. If I let Mission Planner configure the NEO-MP8
  • The Hdop drops to 0,7 - 0,9 - 16 sats
  • When I inject the RTK datas with MP the rover led remains always blue, means no RTK datas
  • Mission Planner 3D Fix label remains the same.
  • Mission Planner reports an error trying to configure GPS 1 but there is only one GPS.

I have updated to latest version of Mission Planner but without solving the problem.

I do not know if the high Hdop value when MP do not configure the GPS is somehow related to the missing RTK fix .
I’m using Windows 7 , it might be a Ublox driver problem ?

you need to update the firmware on your drone to one that supports the m8p

Thanks for replying Michael

I’m using copter 3.4.6.
Is it not supporting M8P ?

Actually for the rover I’m using the same M8P chip of the base , I mean M8P-2 and obviously (to me , but now I have some doubts ) I upload the corresponding Ublox firmware version.
Should I use the M8P-0 Ublox firmware instead because Pixhawk might be unable to recognise the M8P-2 correctly ?

you need 3.5 minimum
https://github.com/ArduPilot/ardupilot/blob/master/ArduCopter/ReleaseNotes.txt#L60

Thanks.

I guessed that the change in 3.5 was only related to the Here+ gps and not to all the M8P family.

I confirm that with version 3.4.6. Ardupilot will not configure correctly the M8P series gps.

Now with 3.5 it works perfectly and Mission Planner shows wonderfull “rtk float” and “rtk fixed” labels instead of Dgps .


Thanks again folks !