[sameer]

Hi
I am using ublox m8n gps with Revo I used u-center  my problem is when i am flying its going toward north !!!
I reconfigure everything is going fine but whenever i fly its going toward north ! i tried flying without gps and it was flying nicely and whenever i connect my gps same problem again happening it is going toward north ! i tried alot but again and again same problem ! please help me how to overcome with this problem !

[TheOtherCliff]

What mode are you flying in with GPS and what mode without GPS.

I bet that you used the transmitter trims to make the quad hover level when flying non-GPS.  Never touch the transmitter trims at all or at least put them back to center after landing.    Instead of changing transmitter trims, you must adjust Attitude -> Settings ->RotateVirtual.
  if it is drifting forward you subtract from pitch
  if it is drifting left you subtract from roll

I bet it was drifting backwards, and you added forward trim on the transmitter to make it stop drifting backwards.  Now the GPS flight mode sees this as you wanting to travel forward all the time.

If you know exactly where your trims were, put them back there and use RotateVirtual to make it hover level with non-GPS (Stabilized1=Attitude) flight mode.

[sameer]

when I am using gps its going north even if i reposition the quadcopter.  flying with non-gps i didnt use transmitter trims its same at the center. its flying properly without using gps. and i tried changing RotateVirtual but still the same going toward north. is it problem with gps or with transmitter or calibration ? 

[TheOtherCliff]

Which GPS mode are you using?  You probably want to use VelocityRoam.

How fast is it going north?  Bad scary fast or just drifting north at say walking speed?

Does it go north when all sticks are in the center?

Is it always north, or it is whatever direction it is pointing when you start?

What kind of mag are you using, what direction is the arrow on it pointing, and what are your 3 mag rotations set to?

Did you change mag error or warning levels, or GPS min satellites or max PDOP?

[sameer]

i am using stabilized. gps ublox m8n
Its going bad scary fast toward north
yh it does go toward north even all sticks are in the center
its always north even if i replace the position of quadcopter it goes only toward north
all 3 mag are set to 0 as default
I didnt change any mag error or warning levels or gps min satellites

[sameer]

i calibrate gps using same procedure
 but end up with such problem going toward north please help me what should i do !

[TheOtherCliff]

Does your GPS have a compass/mag (aux mag)?  Are you using aux mag?  You should be.  Some of Ublox M8N have an I2C compass (aux mag) which must be connected to FlexiPort and configured to FlexiPort in Configuration -> Hardware.

If you have an aux mag as described above, then in Configuration -> Attitude -> Magnetometer your "Mag Usage" should be "Aux Only" and your "Auxiliary Magnetometer Orientation" should be 0,180,0.  Mag Alarms should be usually green.  X axis, Y axis, Z axis should be close to 0, 0, 0 no matter how you slowly rotate / flip the quad around.

Do you know to twist like strands of a rope all the high current wire sets everywhere from battery to motor?

As long as you are using Revo class FC (not CC3D), you don't need to do any GPS setup / configuration.  You don't need to use Ucenter.  Using GCS, after you tell the  what kind of GPS you have and where it is plugged in, everything else is automatic.

I guess you have done mag calibration (Attitude page) and that mag health (Flight Data page) is usually green.  What does the Flight Data page PFD/HUD/ArtificialHorizon thing do when you are in GPS mode (INS13 enabled)?  Is it level and sane (like Basic) or is it crazy twisting all over?

[sameer]

i am using https://www.banggood.com/OpenPiolot-CC3D-Revolution-Flight-Controller-Oplink-M8N-GPS-Distribution-Board-p-1000084.html
I changed the gps configuration back to the default using u-center
when i am using aux mag in FlexiPort then I2C in health(flight data page) is getting red i have changed Configuration -> Attitude -> Magnetometer  "Mag Usage" "Aux Only" and  "Auxiliary Magnetometer Orientation" 0,180,0.  Mag Alarms   X axis, Y axis, Z axis  0, 0, 0 but still its red in hearth(flight data page) and i dont know how to make it green !!!

[sameer]

i look like this whenever i use aux mag I2C

[Jhinta]

that gps doesnt have i2c connected, you need to add two wires (did you do that?)
also if you unlucky that gps module doesnt have a mag chip (read forum)
and i2c needs to be green when hardware is detected, regardless if gps is working or not.

that gps sould have 6 wires, 4 gps / 2 mag, open it up to see whats connected also read the forum about it.
and dont play with u-center your fc does the config for you, so using u-center is useles

https://librepilot.atlassian.net/wiki/display/LPDOC/GPS+setup
see GPS+I2C section

[TheOtherCliff]

First of all you must know that USB only powers the Revo but nothing else.  For anything else to work, you must have flight battery plugged in.

Your mag is black and your I2C is red and your GPS is red X.  Those are all bad.  Yet your mag seems to show that the GPS was working.  It looks like you did some testing with flight battery plugged in, but now (when you made screen capture of health) it is not plugged in.

You do not need to ever touch uCenter ever again.  Revo sets it up all automatically, regardless of how you have it set using uCenter.

Then you need:
- Attitude->Settings->AttitudeEstimationAlgorithm set to INS13
- two wire I2C mag connection (4 wire plug) plugged in FlexiPort
- Hardware page FlexiPort set to I2C
- GPS plugged in MainPort
- Hardware page MainPort set to GPS with speed 57600 and protocol set to UBX
- Attitude->Magnetometer->MagUsage set to AuxOnly and ->MagType set to Flexi
- Attitude->Magnetometer->AuxMagOrientation set to 0,180,0

What does your Flight Data page look like then (when it is outdoors for 10 minutes)?