It's like I have no compass at all?! (APM, mission planner issue)

Donnut

Member
I'm with the HK Micro HKPilot Mega Master Set (http://www.hobbyking.com/hobbyking/...Radio_PDB_BEC_Power_Sensor_EU_Warehouse_.html)

Which is micro APM board and external GPS/compass.
Now the thing is that no matter what I do, cut the jumper to use internal or external compass mission planner always shows the window below.
20160802_135948.jpg
Nothing moves, like there is no compass at all. It always says not enough entry data points at the end.
i've tried
  • Cutting the SJ10 solder point to make it use external compass
  • disconnnecting everything else but the external GPS/Compass to exclusde interferences
  • soldering back the SJ10 blop to keep trying with the internal one
  • ordered whole another board in case my was faulty

all of this results in that window with compas 1 error 99 and nothing moving on the graphs below.
At this point im desperate.
 

LitterBug

Techno Nut
Moderator
Do you have pictures showing your external GPS/Compass and how it is wired to your APM?

Cheers!
LitterBug
 

Donnut

Member
yes here
20160802_192350.jpg


the order of the pins is not noted anywhere, so not sure how to check if it's right. But it came with all the wiring, so I assumed it is right.
However there is one more cable that is the same like this.
 

LitterBug

Techno Nut
Moderator
I recognize the trifecta, but have not worked with the micro apm. From the documentation, it appears you have it wired correctly. So you don't get the following screen when you first go in to compass config?
APMcompass.jpg

Cheers!
LitterBug
 

Donnut

Member
Here are the pinouts to your board:

http://www.hobbyking.com/hobbyking/store/uploads/563792687X846863X56.jpg
http://www.hobbyking.com/hobbyking/store/uploads/680636790X95850X23.jpg

Here's a blown up detail on the trace to cut to disable the internal GPS:
http://www.hobbyking.com/hobbyking/store/uploads/145691547X1818551X39.jpg

Note that I had to cut pretty firmly/deeply to get it disconnected...

Thanks, very useful!

I found the GPS pinout as well
http://www.hobbyking.com/hobbyking/store/uploads/149592509X846863X37.pdf

seems like they are exactly reversed.
But from what I can see only the red wire on my cable goes to the opposite pin on the connector.
But if the wiring is messed up, is it possible for the GPS to have the green led blinking?



edit 2
I just traced each wire individually. All are going where they should according to the pinouts at

http://www.hobbyking.com/hobbyking/store/uploads/563792687X846863X56.jpg
and
http://www.hobbyking.com/hobbyking/store/uploads/149592509X846863X37.pdf

so we can exclude the wiring as the problem I guess
 
Last edited:

Habakkukk

Fly Eagles, Fly!
i could be wrong, but I believe the battery needs to be plugged in for an external compass to work.
 

LitterBug

Techno Nut
Moderator
If you unplug the external compass, does it see one? (just making sure the internal one is deactivated)

Cheers
LitterBug
 

Donnut

Member
no, it doesn't see one.

The odd thing is that I have another of the same board where i resoldered the SJ10 blop and it still does NOT see the internal compass. It behaves the same.
So I have 2 boards with enither external or internal compass working, great huh :)
 

Donnut

Member
I recognize the trifecta, but have not worked with the micro apm. From the documentation, it appears you have it wired correctly. So you don't get the following screen when you first go in to compass config?
View attachment 72767

Cheers!
LitterBug

I do, here it is 20160803_193039.jpg

but when I click to calibrate I always get this

20160802_135948.jpg

No matter if I try internal or external compass, it always doesn't move on the calibration screen and there is compass error 99 on top left


Sometimes this as well,
20160803_193417.jpg


so far seems like GPS can't see even one SAT either.
 

Donnut

Member
- I reflashed the firmware, no improvement
- checked for continuity the SJ10 blop, it's definitely cut
- I also checked for continuity the SJ10 on the other apm mini that I resoldered, it's connected. Both don't have neither internal or external compass working

what else it might be?
 

makattack

Winter is coming
Moderator
Mentor
As rare as it might seem, it's entirely possible you have two defective boards. I had bad luck, when I started experimenting with APM, with one vendor on eBay who sent a board that wouldn't register any compass values. I ended up determining it was a bad i2c bus, which meant that neither the built in nor external compass would work. I verified this by directly connecting a known working compass to the i2c bus and not seeing any values read by the software.

Are you able to get the vendor to refund or replace your board? Unfortunately, I couldn't get the ebay vendor to do that, so I simply repurposed that board to be a "hardware in the loop" simulator board for mucking around.
 

Donnut

Member
As rare as it might seem, it's entirely possible you have two defective boards. I had bad luck, when I started experimenting with APM, with one vendor on eBay who sent a board that wouldn't register any compass values. I ended up determining it was a bad i2c bus, which meant that neither the built in nor external compass would work. I verified this by directly connecting a known working compass to the i2c bus and not seeing any values read by the software.

Are you able to get the vendor to refund or replace your board? Unfortunately, I couldn't get the ebay vendor to do that, so I simply repurposed that board to be a "hardware in the loop" simulator board for mucking around.

well the vendor is hobbyking and I guess I could send it back for a refund, but not sure what is the case when I have the SJ10 cut.
Anyway, would prefer to just get it working somehow, or make sure boards are DOA