[CMOL]

Hi,
I'm not sure if you can help me, but the problem I am having is that everytime I try to disarm my quad it doesn't do anything. In Librepilot I have managed to get my GPS Ublox M8N and Revolution to work well together, but then after a short while it all fails and the ATTI, STAB & MAG all turn red, which we're all green before.
I been reading everything I can get my hands on, but the problem still remains the same.
(I have a Taranis X9D 16CH transmitter and a X8R receiver)
All I want to achieve is to make my quad to be able to return to home by the flick of a switch OR if I loose connection to the aircraft. I was also attempting to be able to use the position hold function.
I would be very happy if someone can help me with this tricky but interesting problem.
Thanks in advance 
//CMOL

[rotomoto]

Also tried to solve this puzzle over the weekend. Looks like you need magnetometer moved outside the FC. There are too many issues with integrated mag. V9 GPS was a Openpilot solution, but it is not available anywhere.
 Next Libreoffice release will hopefully solve this problem with support to external mag. Maybe then we can use some of those GPS+mag pugs out there.

[TheOtherCliff]

It really sounds (red mag causes other things to be red) like you have mag problems.  You need a careful mag calibration (see Mag Calibration section here https://librepilot.atlassian.net/wiki/display/LPDOC/Aux+Mag+Setup+and+Calibration )

If everything looks good until the motors are running hard, then you need to address the mag fields from your wiring.

[hwh]

...Next Libreoffice release ...

I use LibreOffice too but I never thought it supported gps units or revos 

[CMOL]

What is the V9 GPS, would it solve my problem?

[hwh]

What is the V9 GPS, would it solve my problem?

The OpenPilot v9 gps (also called the Platinum gps) was made by the original project (now defunct) but is no longer available except for occasional used ones that pop up for sale.

The next release of LibrePilot will support two replacements, gps units with two cables (one for gps, one for mag) and also Naza type gps units that combine gps and mag in one cable.

Would it solve your problem?  Maybe.  You should still follow Cliff's advice and twist all your cables to minimize their magnetic fields.

[CMOL]

http://www.banggood.com/Ublox-NEO-M8N-GPS-For-Mini-CC3D-CC3D-Atom-CC3D-Revolution-Flight-Controller-Built-in-Compass-p-999341.html

This GPS is the one I have, many people have got it working with position hold and RTH whilst using a Revo. How have they done it you think?

[hwh]

http://www.banggood.com/Ublox-NEO-M8N-GPS-For-Mini-CC3D-CC3D-Atom-CC3D-Revolution-Flight-Controller-Built-in-Compass-p-999341.html

This GPS is the one I have, many people have got it working with position hold and RTH whilst using a Revo. How have they done it you think?

That appears to be one of the gps units that while they may have a compass inside it's not connected to the cable.  Someone else (Cliff?) mentioned them, if you want to use the compass part you have to add a cable and connector for it.  If you look at the GCS screen picture they posted you can see that while GPS is green, mag is black (no mag available).

Twisting the power cables to minimize their magnetic fields is even more necessary using the revo's onboard mag sensor than when using an external mag.  Some vehicles can't get the interference from the power wires low enough to get reliable mag from the revo's onboard mag, that was the reason for the external mag sensors in the gps units.

Have you gone through the complete sensor calibration as shown at https://librepilot.atlassian.net/wiki/display/LPDOC/Sensor+calibration ?     

[CMOL]

http://www.banggood.com/Ublox-NEO-M8N-GPS-For-Mini-CC3D-CC3D-Atom-CC3D-Revolution-Flight-Controller-Built-in-Compass-p-999341.html

This GPS is the one I have, many people have got it working with position hold and RTH whilst using a Revo. How have they done it you think?

That appears to be one of the gps units that while they may have a compass inside it's not connected to the cable.  Someone else (Cliff?) mentioned them, if you want to use the compass part you have to add a cable and connector for it.  If you look at the GCS screen picture they posted you can see that while GPS is green, mag is black (no mag available).

Twisting the power cables to minimize their magnetic fields is even more necessary using the revo's onboard mag sensor than when using an external mag.  Some vehicles can't get the interference from the power wires low enough to get reliable mag from the revo's onboard mag, that was the reason for the external mag sensors in the gps units.

Have you gone through the complete sensor calibration as shown at https://librepilot.atlassian.net/wiki/display/LPDOC/Sensor+calibration ?     

Yes, I have gone through the calibration. But wouldn't it work if I bought an external compass that I could connect via the flexi port?

[CMOL]

Just a quick update,
I have found this: http://www.digikey.se/product-detail/en/CGGP.25.4.A.02/931-1126-ND/2690283

I think this is the GPS people have been naming platinum GPS or V9.

[hwh]

Just a quick update,
I have found this: http://www.digikey.se/product-detail/en/CGGP.25.4.A.02/931-1126-ND/2690283
I think this is the GPS people have been naming platinum GPS or V9.

That's the patch antenna that's used on the V9, not a whole V9 gps.  It would be really nice if that were the whole gps, it works out to cost about $5 (USD). The V9 isn't made anymore and were never sold through any distributors.  The only way to get one is to find one for sale in places like the "for sale" area on rcgroups.com.

This is what the V9/Platinum GPS looks like:

[CMOL]

But isn't the Ublox M8N GPS from bang good better than this one? Because this one doesn't include a compass, or does it?

[CMOL]

I have found this
http://www.aliexpress.com/item/Ublox-NEO-7N-GPS-With-3-Axis-Electronic-Compass-For-CC3D-Revolution-Flight-Controller-Black-GPS/32434783219.html?spm=2114.10010108.100010.1.3ODGWS
I thought it looked interesting since it had two cables coming out of it which probably means that one is for the GPS and the other is for the compass.
Would this be worth buying? But how would I set up an external compass in LibrePilot?
Regards,
CMOL

[hwh]

But isn't the Ublox M8N GPS from bang good better than this one? Because this one doesn't include a compass, or does it?

The V9 is the original gps with compass for OpenPilot.   It not only has a compass, it sends the compass data down the same wire as the gps data so it only uses one port on the revo.  Until Cliff wrote the Naza gps decoder that's in the next release it was the only way to get gps and compass on one port.  Now we have another option for using just one port, the Naza gps lite or one of it's clones.   The next best choice would be one of the gps/compass units that has two cables, one for gps and one for compass.  Those are also supported in the next release.  Both are also in the "next" branch in the source tree if you want to compile your own version before the official release.  Neither of these options comes with the correct connector for the revo/sparky2/cc3d so you have to change the connector.

The V9 has 3 connectors but normally you only use one of them.  One is the combined gps/mag data (used for revo/sparky2), one just gps data (for cc3d and other brand flight controllers), and the third is a debugging port for developers.

The banggood one you posted a link to doesn't seem to have the second cable that's required for the compass data on anything but the V9 or Naza gps units.  That particular one is also a bit overpriced.  This one, http://www.banggood.com/Ublox-M8N-GPS-Compatible-with-DJI-NAZA-Lite-V1-V2-Flight-Controller-Phantom-1-2-Vision-p-991718.html is one of the Naza clone gps units that Cliff's new code supports for both gps and compass.  You just need to change the connector, most people just buy short cables with the connector on eBay and splice them onto the existing cable.  The connector pins are really, really tiny and hard to crimp even if you have the correct crimper.

[hwh]

I have found this
http://www.aliexpress.com/item/Ublox-NEO-7N-GPS-With-3-Axis-Electronic-Compass-For-CC3D-Revolution-Flight-Controller-Black-GPS/32434783219.html?spm=2114.10010108.100010.1.3ODGWS
I thought it looked interesting since it had two cables coming out of it which probably means that one is for the GPS and the other is for the compass.
Would this be worth buying? But how would I set up an external compass in LibrePilot?
Regards,
CMOL

You posted a few seconds before I did.  That one is one of the two cable ones I was talking about.  It looks like it may even have the correct connectors on it, it's hard to tell for sure from the pictures but they seem to say it does.

That's the type gps that the link in Cliff's earlier post was talking about setting up, an I2C aux mag.   The compass part isn't supported in the current released version, only in the next one or if you compile your own from the next branch in the source.

Either that one or the one I posted should work fine.  The choice is using one port or two and maybe changing the connector or not.