LibrePilot Forum

Development => Hardware => Topic started by: remis on September 26, 2019, 08:54:08 am

Title: compatible external compas
Post by: remis on September 26, 2019, 08:54:08 am
Hi,
I’d like to found a compass compatible with librepilot : no more using the internal compass for better GPS hold.
The HMC5883L seem to be compatible. But it is no more avalable. Sellers says « HMC5883 » but it is always a QMC5883 with different register and adress configuration.
Witch compas is compatible with libre pilot, today ?
Many thanks
Title: Re: compatible external compas
Post by: jdl on September 26, 2019, 01:27:32 pm
Hi,
An year ago I bought few modules GY-273 with genuine HMC5883L chips from an ebay seller diybox.

https://www.ebay.com/itm/HMC5883L-GY-271-GY-273-Triple-Axis-Compass-Magnetomet-Sensor-3V-5V-for-Arduino/112527675935?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.com/itm/HMC5883L-GY-271-GY-273-Triple-Axis-Compass-Magnetomet-Sensor-3V-5V-for-Arduino/112527675935?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)

Option: GY-273 Original

I had placed a note with my order:

Quote
Note to seller
Hi, please check if the chip on the modules is exactly HMC5883L (marked L883), just as on the photo in item description. I DON'T NEED QMC5883 chip (usually marked as DA5883)! If you cannot supply the boards with L883 chips (that are the genuine HMC5883L from Honeywell), please cancel the order and refund me to save the unnecessary waiting and opening case afterwards. Thanks! Kind Regards, .....
  :)


Looks like he still sells them...
Title: Re: compatible external compas
Post by: remis on September 26, 2019, 04:29:35 pm
Many thanks for your link .
 I will try.
The reference on the IC could be the only confirmation of true HMC5883...It is more difficult to change it..
Regards
Title: Re: compatible external compas
Post by: remis on September 27, 2019, 02:46:55 pm
Hi,
The seller refund me....thus i conclude that HMC5883L is no more available.

The question remain:
Which external compass is compatible with libre pilot ( except HMC5883L..)

Remi
Title: Re: compatible external compas
Post by: TheOtherCliff on September 28, 2019, 12:07:29 am
I think it's likely that the seller refunded because he did not want to (or didn't know how to) check the IC number.

I would think we can't guess as to whether HMC5883L is available.  :)
Title: Re: compatible external compas
Post by: remis on September 28, 2019, 08:05:40 pm
It is easy to read the IC reference. I confirm with mine is a QMC version. Confirmed with JDL note
The HMC5883L from Honeywell is no more in production. This IC is 0 stock in Digikey, Farnel and others.
All facs confirmed the end of the product.

The question remain the same : Is there other magnetometer compatible with librepilots?

Remi

Title: Re: compatible external compas
Post by: remis on September 28, 2019, 08:55:28 pm
I answer : no. Because the on board compas is a true HMC5883L . The combo GPS and Compass should use HMC5883. I can understand that software is not dsigned to choose different compass reference.
Title: Re: compatible external compas
Post by: TheOtherCliff on September 28, 2019, 11:23:25 pm
Seems the HMC5883L stock is worse than MPU6000 / MPU6050 / MPU9250 which are all EOL/NRND for years now, yet FC boards that use them are still being built.  I thought that for instance digikey did not have any of these years ago.  Now I see that they do have some (MPUxxxx).

I recall a year or more ago that a developer thought to make the LibrePilot mag driver automatically recognize HMC5883L or QMC5883, but it never happened.  I don't see any git log comments in next or tracking about this.  It is possible that it is done in a private branch somewhere though.

I suspect that most people who want mag now use the DJI/Naza GPS/mag which is supported by LibrePilot.  This GPS/mag uses one port for both GPS and mag.  That leaves more ports free for other things like OSD.  Also, with I2C mag (HMC5883L) there are sometimes issues with I2C bus termination (pullups) requiring users to solder some stronger pullup resistors.  The DJI/Naza GPS/mag also appears to be EOL since 2016, but are still available.
Title: Re: compatible external compas
Post by: jdl on September 30, 2019, 01:04:26 pm
Another option may be a GPS/MAG combo like Beitian BN-880. I've used it in the past, its mag chip was (this may have to be confirmed for units being currently on sale) HMC5883L and worked very well (on I2C).
Title: Re: compatible external compas
Post by: remis on October 09, 2019, 09:56:37 pm
I found one !
https://www.ebay.fr/itm/GY-273-HMC5883L-GENUINE-L883-3-Axis-Compass-Magnetometer-Module-Arduino-SOLDERED/282695196953?ssPageName=STRK%3AMEBIDX%3AIT&var=581923261969&_trksid=p2057872.m2749.l2649

with on board 3v3 regulator and 4k7 I2C pull up. Need only one connector to flexi port.
GUI config : Must be connected to flexi port in I2C mode, flexi.
Title: Re: compatible external compas
Post by: TheOtherCliff on October 10, 2019, 02:06:40 am
I just ordered one of these for about USD $1.40  I might try on aircraft where I have magnetic cowl latches, to move it far away from the magnets.  It looks right.  I will confirm that it works, try a 1m cable, and report back within a couple months (cheap price but 2 months shipping time).

https://www.ebay.com/itm/GY-273-HMC5883L-Triple-Axis-Compass-Magnetometer-Sensor-Module-For-ArduinoPLCA/223610646034
Title: Re: compatible external compas
Post by: jdl on October 10, 2019, 10:34:56 am
I found one !
https://www.ebay.fr/itm/GY-273-HMC5883L-GENUINE-L883-3-Axis-Compass-Magnetometer-Module-Arduino-SOLDERED/282695196953?ssPageName=STRK%3AMEBIDX%3AIT&var=581923261969&_trksid=p2057872.m2749.l2649

with on board 3v3 regulator and 4k7 I2C pull up. Need only one connector to flexi port.
GUI config : Must be connected to flexi port in I2C mode, flexi.

Seems ok on the photo. A word of caution: better DO NOT use header pins that come with the module, they are quite often cheapest possible, steel inside, and will affect the magnetometer. Better solder cables directly to the pads. Or at least test header pins while still not soldered with a strong magnet, if they stick to it, better don't use them.

I just ordered one of these for about USD $1.40  I might try on aircraft where I have magnetic cowl latches, to move it far away from the magnets.  It looks right.  I will confirm that it works, try a 1m cable, and report back within a couple months (cheap price but 2 months shipping time).

https://www.ebay.com/itm/GY-273-HMC5883L-Triple-Axis-Compass-Magnetometer-Sensor-Module-For-ArduinoPLCA/223610646034

I'm afraid the module from this link has QMC5883 instead. If photos are correct, the marking DA5883 reveals it.
Title: Re: compatible external compas
Post by: TheOtherCliff on October 10, 2019, 08:29:39 pm
Ah well...  I can get a refund or maybe keep it and update the code to auto-detect and work with either mag.
Title: Re: compatible external compas
Post by: f5soh on October 11, 2019, 12:11:09 am
Like here, maybe ?

https://bitbucket.org/librepilot/librepilot/pull-requests/496
Title: Re: compatible external compas
Post by: TheOtherCliff on October 11, 2019, 09:58:49 pm
Great!

I did mention earlier that I thought someone was working on it, but I did not see it in next yet.
Title: Re: compatible external compas
Post by: jdl on June 01, 2020, 10:15:12 am
Report:

I've just received two GY-273 modules I've ordered a month ago from ebay and they have GENUINE HMC5883L chips (L883 markings).
Seller is fr_aurora:

https://www.ebay.com/itm/263478814000 (https://www.ebay.com/itm/263478814000)

GY-273
Original

These modules are tiny and perform very well as Auxmag (I2C) for Revo FC.