GPS orientation
« on: November 02, 2016, 02:41:39 pm »
Attached is a photo of the new uBLOXNEO-M8N I'm planning on installing in a resurrected 2 m Telemaster for a camera platform.  In the attached photo the red circle has a tick mark.
Does this tick mark have to be oriented in any specific direction compared to aircraft heading?
Thanks

f5soh

  • *****
  • 4572
    • LibrePilot
Re: GPS orientation
« Reply #1 on: November 02, 2016, 02:55:17 pm »
This tick should be heading forward.
Whatever the orientation, you need to adjust the AuxMag orientation.
Should be Roll:180° + Yaw:180° or just equivalent using Pitch:180° with tick forward.

Just a question: Do you have the AuxMag I2c extra wires to be connected to the flexiPort ?

QC102

  • **
  • 84
Re: GPS orientation
« Reply #2 on: November 03, 2016, 05:40:03 am »
This tick should be heading forward.
Whatever the orientation, you need to adjust the AuxMag orientation.
Should be Roll:180° + Yaw:180° or just equivalent using Pitch:180° with tick forward.

Just a question: Do you have the AuxMag I2c extra wires to be connected to the flexiPort ?

I also have the same GPS... rather that hijack the thread..   can you take a look at my  post please..

https://forum.librepilot.org/index.php?topic=2571.0     

Re: GPS orientation
« Reply #3 on: November 03, 2016, 06:12:50 pm »
These generic GPS modules that also say "compass" are kind of sketchy.  Sometimes they only have a serial connection to the GPS, and the I2C interface to the magnetometer is not even wired up.  Sometimes, the magnetometer chip is not even populated on the board.  Ideally, what you want is a module with a microcontroller that will combine GPS and mag data onto a single serial connection using the DJI protocol. 

It's impossible to tell what you have unless you open it up.  Take it apart and take some pictures, and post them here.  Then we can tell you what you have.
 

Re: GPS orientation
« Reply #4 on: November 04, 2016, 06:43:53 pm »
Belated response -
The GPS module has only 4 wires, which, I presume, means that magnetic data is not sent to the Revo board.  The connector at the module is a 6 pin connector, so I could probably cannibalize a couple of wires from another connector to add to the GPS bundle.  There are a few issues that I anticipate in trying to do so:
1. I don't know how to extract the wires and their terminals from the tiny connectors without damaging them.
2. I don't know the pinout of the GPS module.
3. I was planning on using the Flexi port for OSD signals, so using it for mag data would preclude that option.
4. I use PWM signals from my receiver to the Revo, so the Flexi-IO port is not an option, unless I can figure out how to use PPM to free up the extra Flexi I/O pins.
 

f5soh

  • *****
  • 4572
    • LibrePilot
Re: GPS orientation
« Reply #5 on: November 04, 2016, 06:58:51 pm »
For wires, take a look at this post / video:
https://forum.librepilot.org/index.php?topic=1110.0

This assumes the mag chip is populated and working fine.