mRo M8N GPS with 1.5.3 firmware

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Hi Guys,

Did you noticed that amount of reported sats are less than on stock solo firmware?
By stock solo firmware I mean last published firmware from 3DR.

On stock I got more than 20 sats in my area, on 1.5.3 I got 16.
 
I after we'll try to pano-sphere back lowered the firmware to 1.3.1
 
Hi Guys,

Did you noticed that amount of reported sats are less than on stock solo firmware?
By stock solo firmware I mean last published firmware from 3DR.

On stock I got more than 20 sats in my area, on 1.5.3 I got 16.

No, but it's possible. @Pedals2Paddles @Xor @cynfab Do you guys remember seeing anything about sats in the code? I don't...
 
I got reply from Jordi:

Hello Tomasz,

We will check it out but maybe is because firmware 1.5.3 is resetting the GPS and by resetting the GPS the Galileo constellation gets deactivated.
 
[QUOTE = "n01kn0ws, почта: 106291, член: 5070"] Привет Дмитрий,

Pano sphera:ERROR
 
Last edited:
[QUOTE = "n01kn0ws, почта: 106291, член: 5070"] Привет Дмитрий,

Я ТОК сферические панорамы 2 дня назад на 1.5.3 и он правильно работал. Какие вопросы вы получили? [/ QUOTE]
Pano sphera:ERROR
I'm afraid that I don't speak in your language :/
 
Hi Guys,

Did you noticed that amount of reported sats are less than on stock solo firmware?
By stock solo firmware I mean last published firmware from 3DR.

On stock I got more than 20 sats in my area, on 1.5.3 I got 16.
Interesting. I recently updated to 1.5.3 and noticed less reported satellites. However I've only flown twice since the update (not a good sample size) so I did not think anything of it.
 
Good to hear that I'm not the only one :)
But seriously, I flown many times and in different locations with 1.5.3 and never get more than 16 sats.
When I flown on 1.3.1 I got 20 or more.
 
The code in Ardupilot/copter 1.5.3 that deals with the GPS:
-rw-r--r-- 1 kenm kenm 26207 Feb 26 12:30 AP_GPS_UBLOX.cpp
-rw-r--r-- 1 kenm kenm 10242 Feb 26 12:30 AP_GPS_UBLOX.h
is identical to that from 1.3.1.

With that said, there is code to save the configuration:
#define SAVE_CFG_ALL (SAVE_CFG_IO|SAVE_CFG_MSG|SAVE_CFG_INF|SAVE_CFG_NAV|SAVE_CFG_RXM|SAVE_CFG_RINV|SAVE_CFG_ANT)

The MrO board that I got was configured for Galileo as well as GPS & GLONASS. When the 1.3.1 firmware configured the GPS, it did not change that config. I have not reviewed the AP_GPS_UBLOX.cpp code in detail, but I also have some other M8N receivers (real ones not fake) and the factory config did NOT come with Galileo enabled. So I could imagine a case where an MrO might have slipped through with Galileo not being enabled.
Paragraph 1.5 of NEO-M8-FW3_DataSheet_(UBX-15031086).pdf

says Galileo is NOT enabled as the default configuration.

The best way to tell would be to remove the MrO and read out the saved config using u-Center. If Galileo is not enabled then enable it and save the config to BBRAM and Flash.
In my case, I read out the config before I ever put the MrO into the Solo and I did it again after the Solo had re-configured it. Galileo was enabled initially and was still enabled after the Solo re-configured it.
 
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The code in Ardupilot/copter 1.5.3 that deals with the GPS:
-rw-r--r-- 1 kenm kenm 26207 Feb 26 12:30 AP_GPS_UBLOX.cpp
-rw-r--r-- 1 kenm kenm 10242 Feb 26 12:30 AP_GPS_UBLOX.h
is identical to that from 1.3.1.

With that said, there is code to save the configuration:
#define SAVE_CFG_ALL (SAVE_CFG_IO|SAVE_CFG_MSG|SAVE_CFG_INF|SAVE_CFG_NAV|SAVE_CFG_RXM|SAVE_CFG_RINV|SAVE_CFG_ANT)

The MrO board that I got was configured for Galileo as well as GPS & GLONASS. When the 1.3.1 firmware configured the GPS, it did not change that config. I have not reviewed the AP_GPS_UBLOX.cpp code in detail, but I also have some other M8N receivers (real ones not fake) and the factory config did NOT come with Galileo enabled. So I could imagine a case where an MrO might have slipped through with Galileo not being enabled.
Paragraph 1.5 of NEO-M8-FW3_DataSheet_(UBX-15031086).pdf

says Galileo is NOT enabled as the default configuration.

The best way to tell would be to remove the MrO and read out the saved config using u-Center. If Galileo is not enabled then enable it and save the config to BBRAM and Flash.
In my case, I read out the config before I ever put the MrO into the Solo and I did it again after the Solo had re-configured it. Galileo was enabled initially and was still enabled after the Solo re-configured it.

Hi Cynfab.

It would be true what you are saying about galileo not enabled if I would not get more than 15 - 16 sats on stock firmware 1.3.1

When I got mRo I consulted which settings are enabled on this GPS with Jordi. He confirmed that they are enabling galileo support on each device.

When I installed mRo GPS on fw 1.3.1 I got more than 20 stats in my area, sadly it was changed when I upgraded fw to 1.5.3 and now I can see 15 - 16 sats.

As Jordi mentioned is somehow fw 1.5.3 resetting GPS settings so it is wiping custom settings applied on GPS so only default values are enabled? :(
 
Yep, that certainly is puzzling. It would still be interesting to see how the mRo is configured now that you have installed and flown 1.5.3.
Without hands on, it is hard to diagnose too much from afar.
 
Just pulled my M8N out of my FrankenSolo which does fly with 1.5.3. and read out the config with u-center. It is still set for Galileo. I had been flying it with 1.3.1 and updated to 1.5.3. I can't say if my # of sats changed from one version to the other, but I can say that the 1.3.1-->1.5.3 update process did not change my M8N's Galileo setting in UBX-CFG-GNSS. This is NOT however an mRo. it is a stock Solo's GPS board that I replaced the NEO-7N with an M8N. I also removed the external SAW and changed the antenna to one that supported GLONASS. Not quite an apples-->apples comparison, but my M8N is the same rev # as the one on my mRo.
 
Took the laptop & battery tray/GPS outside and sat it on the ground, 20 sats in the solution. See attached pix. Of course this is NOT on an operating Solo, so YMMV ;>))
 

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I'm wondering now how mRo is different than yours. If they modified settings in GPS itself to enable galileo then resetting settings by firmware could potentially revert to default settings.
 
Has anyone confirmed the satellite delta by switching back to fw 1.3.1? If so, did it jump back to 20+ satellites when switching back to 1.3.1?
 
One other thing to consider is that the Solo configures the GPS to give a 5Hz navigation rate. That works fine for GPS and GPS + GLONASS. But if you add Galileo, the M8N when running its firmware from Flash, can only manage 3Hz navigation rate.
See section 4.12
https://www.u-blox.com/sites/default/files/GNSS-FW3.01_ReleaseNotes_(UBX-16000319)_Public.pdf

I have not been able to determine what navigation rate is possible if the M8N is running its firmware from ROM, but my FrankenSolo's M8N has version 2.01 in ROM and 3.01 in Flash, as does the one I got from mRo. The most recent M8N's I got from DigiKey are 3.01 in ROM (and probably the recent ones from mRo are too)
What does this mean, as Solo's do fly with M8N's configred for GPS + GLONASS + Galileo?
I don't really have a good idea, that may be a question for a u-blox FAE.
 
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