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Root GPS.conf fix for LG Volt as of 4/9/2015

I couldn't ping the xtra server with the http in front of it, nor could I with anything after ".net".

The ntp servers pinged just fine without the http (as written in the gps.conf file)

I'm going to try changing my gps.conf file to just 'xtra1.gpsonextra.net' and see if that helps speed up lock.
 
I've changed my gps.conf file to the following after failing to get a ping with http in front of it :

Code: 
XTRA_SERVER_1=xtra1.gpsonextra.net
XTRA_SERVER_2=xtra2.gpsonextra.net
XTRA_SERVER_3=xtra3.gpsonextra.net

ERR_ESTIMATE=0

NTP_SERVER=north-america.pool.ntp.org
NTP_SERVER=0.north-america.pool.ntp.org
NTP_SERVER=1.north-america.pool.ntp.org
NTP_SERVER=2.north-america.pool.ntp.org
NTP_SERVER=3.north-america.pool.ntp.org
NTP_SERVER=us.pool.ntp.org
NTP_SERVER=0.us.pool.ntp.org
NTP_SERVER=1.us.pool.ntp.org
NTP_SERVER=2.us.pool.ntp.org
NTP_SERVER=3.us.pool.ntp.org

DEBUG_LEVEL = 5

INTERMEDIATE_POS=0

CAPABILITIES=0x37

## the following can be set to 3 or 1 with same results as long as you don't have supl enabled  
LPP_PROFILE = 3

NMEA_PROVIDER=1

A_GLONASS_POS_PROTOCOL_SELECT = 0x4

VENDOR=SPR

LGE_GPS_POSITION_MODE=0
 
jfuginay said:
No problem, and you're right about the accuracy threshold being related to the intermediate position, but a 0 doesn't mean off, if you want off on that value you need to hashtag it (or delete the line all together)
Click to expand...
According to FasterGPS, it means disabled.
 
bg4m3r said:
According to FasterGPS, it means disabled.
Click to expand...

I think I'm having trouble communicating which one I'm talking about. A value of '0' does mean disabled for the "Intermediate Position", but a value of "0" doesn't mean off or disabled when it relates to "Accuracy Threshold". A zero after accuracy threshold will allow all positions, the only way to disable the accuracy threshold is to place a hashtag infront of it.

For example, if I want my Ingress game to open up and show a location without waiting until a decent lock, I would set the following:

Intermediate Position = 1
Accuracy Threshold= 5000

This would allow for 'dirty' position data to be used to report my position in the mean time while the gps is getting a fix. Any location received that is outside of the accuracy threshold (5000) would be discarded, while anything within the threshold would be used as a reportable location for your device.

This is just from my understanding of it, it could totally be the case that if you disable Intermediate position, a 0 on accuracy threshold will disable that too, I'm not 100 percent sure, just brainstorming outloud with ya'll.
 
bg4m3r said:
Have you seen this?
http://forum.xda-developers.com/showthread.php?t=2198319
Click to expand...

Yep, that's where I got the 'derekgordon' ntp and xtra servers. I didn't have good results with any of the versions available with that app. It recommends the Google version which attempts to enable supl support on our devices, but does so with code which has in my tests shown to be not readable by our devices.

Even the 'no supl' version with that app didn't provide good results in my tests. I would get a quick lock, but the gps wouldn't follow me around anymore.

I even tried the LG specific versions of that app's gps conf and supl cert files, as I mentioned earlier, the supl cert files are likely a placebo, as we are likely just getting our agps data from the ntp and xtra servers (likely just the ntp servers, as the http:// infront of the xtra servers is most likely making our devices fail to get any data from them when using the default configuration given by topNTP)
 
jfuginay said:
I think I'm having trouble communicating which one I'm talking about. A value of '0' does mean disabled for the "Intermediate Position", but a value of "0" doesn't mean off or disabled when it relates to "Accuracy Threshold". A zero after accuracy threshold will allow all positions, the only way to disable the accuracy threshold is to place a hashtag infront of it.
Click to expand...
I agree with what you're saying. But if intermediate positioning is disabled and the accuracy threshold only relates to intermediate positioning, then it wouldn't matter what accuracy threshold is set to because the function it interacts with is disabled.
Basically, as I am understanding, accuracy threshold fine tunes the intermediate position.
 
bg4m3r said:
I agree with what you're saying. But if intermediate positioning is disabled and the accuracy threshold only relates to intermediate positioning, then it wouldn't matter what accuracy threshold is set to because the function it interacts with is disabled.
Basically, as I am understanding, accuracy threshold fine tunes the intermediate position.
Click to expand...

Sounds legit.

I think I change my mind about whether to add http in front of the xtra servers. Was losing my gps lock every 30 secs until I put the full address back in.

Makes me wonder two things; why we don't include http in front of NTP servers and if we should.
 
jfuginay said:
Sounds legit.

I think I change my mind about whether to add http in front of the xtra servers. Was losing my gps lock every 30 secs until I put the full address back in.

Makes me wonder two things; why we don't include http in front of NTP servers and if we should.
Click to expand...
If you throw that xtra server address into your web browser, it actually downloads the bin file listed. I think it may be providing agps assist data?
 
bg4m3r said:
If you throw that xtra server address into your web browser, it actually downloads the bin file listed. I think it may be providing agps assist data?
Click to expand...

Yeah, probably, getting a much faster and more stable lock with full xtra address in there, as well as with the multiple NTP servers.

Also changed my LPP profile to 3. Seems to make my GPS perform a little better, not exactly sure how though. My thought is that perhaps xtra and NTP are in separate categories. For example, ntp being user plane and xtra being control plane( or vice versa), thus, enabling both user and control plane would mean use them both?

It seems like supl probably is not the only user plane agps method.

It could also be that control plane is our device (gps) and user plane is any of the supl/xtra/c2k stuff (agps )

So when we did LPP profile 1, it improved performance by disabling the agps attempts over a gsm network and enabled our GPS to attempt to download agps data over the CDMA network via 3g or 4g/LTE

Perhaps changing to LPP= 3 we further enabled user plane assistance such as NTP, xtra, and allegedly supl.
 
I have had a good performance boost while playing ingress when I switch the NMEA provider from modem processor ( "1" ) to application processor ( "0" )

Google maps picks up my location regardless, I have a feeling that GMaps is strong enough to evoke our modem processor to start our gps up, but for some reason Ingress won't keep my gps active by itself for very long, unless I switch this setting.

I'm making sure to test the settings out on both Gmaps and Ingress before noting the performance of a particular setting change. I had to redo a lot of tests which were done solely with Ingress, and Ingress is not anywhere near as good as Gmaps at locating your position and following you.

It looks like the "KISS" saying applies to our gps.conf file. Instead of putting 50 NTP servers on there, just Keep It Simple, Stupid!
 
I've been using the GPS.conf for a while and Ingress is a bit faster to lockon when I do play, Great work there jfuginay. I'll have to try out the simpler "KISS" file later today.
 
I noticed that you removed two of the xtra servers from the conf. This for me curious about the address and the reason for there being 3 of them. I put the following in my browser:
xtra.gpsonextra.net/xtra.bin
xtra.gpsonextra.net/xtra2.bin

Both download a different bin file (I checked the md5s). I haven't tried to look inside them. Not sure if I would be able to make anything out if I did, but it might be worth having both those listed in pave of the one there now.
Interesting... I just checked the xtra2.bin from my address above against the one from your file. They don't match either, so the xtra1 subdomain is actually providing a different resource. Same with the xtra2 (checked), and presumably, xtra3 subdomains.
What do we know about these files? Why is the xtra2.bin specifically listed on our conf? Could be a regional thing.
There is also an xtra4 subdomain with a bin file for download, but no 5, which matches up with the 5 available entries in faster GPS.
 
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OtaconEmmerich said:
I've been using the GPS.conf for a while and Ingress is a bit faster to lockon when I do play, Great work there jfuginay. I'll have to try out the simpler "KISS" file later today.
Click to expand...

Don't be alarmed if it takes longer to lock the first time you try it; I've noticed my first lock takes a little longer when switching NMEA provider from modem to application, but locks after the first are really fast and my over all performance ( ingress not showing me as driving through houses) is better. I get a lock to within 25 feet inside my house.

I've noticed (while trying to screenshot my awesome GPS lock) that my quality of communication with the GPS satellites gets worse when I touch my phone; this could be a potential problem for holding it to ingress, not so much a problem while cargressing I guess.

Nothing too bad, high 20s instead of low 30s, still worthy of noting though. Not sure if it had anything to do with my flip case, will test out more later.

The two pics are from in my house, one not holding and one with holding my phone.
 

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Just did a test on what I was talking about in my last post. My GPS had been bring flaky the past few days using the setup from the first post. This is what my conf file looks like right now:

Code: 
 XTRA_SERVER_1=http://xtra.gpsonextra.net/xtra2.bin
XTRA_SERVER_2=http://xtra1.gpsonextra.net/xtra2.bin
XTRA_SERVER_3=http://xtra2.gpsonextra.net/xtra2.bin
XTRA_SERVER_4=http://xtra3.gpsonextra.net/xtra2.bin
XTRA_SERVER_5=http://xtra4.gpsonextra.net/xtra2.bin

NTP_SERVER=us.pool.ntp.org
NTP_SERVER=north-america.pool.ntp.org

DEBUG_LEVEL=2
INTERMEDIATE_POS=0
CAPABILITIES=0x37
LPP_PROFILE=1
NMEA_PROVIDER=0
A_GLONASS_POS_PROTOCOL_SELECT=0x4
VENDOR=SPR
LGE_GPS_POSITION_MODE=0

And this is what I had for a lock inside a panel van going 70mph, holding the phone in the center of the van within 5 seconds of opening GPS Test and clearing/updating AGPS data:
 

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I tried using LPP_PROFILE=0 and A_GLONASS_POS_PROTOCOL_SELECT=0x2, GPS refuses to work at all.
I reverted back to 0x2 and 1 and it all comes back.(at least what I can get a lock on with the cloudy day we have today)
 
bg4m3r said:
I had that issue too.
Click to expand...

How long did you give it before giving up? My very first lock took a very long time, at least 5 min. But subsequent locks are a lot faster, and the precision improved from within 30-40 feet to within 20-30 feet.

bg4m3r said:
I noticed that you removed two of the xtra servers from the conf. This for me curious about the address and the reason for there being 3 of them. I put the following in my browser:
xtra.gpsonextra.net/xtra.bin
xtra.gpsonextra.net/xtra2.bin

Both download a different bin file (I checked the md5s). I haven't tried to look inside them. Not sure if I would be able to make anything out if I did, but it might be worth having both those listed in pave of the one there now.
Interesting... I just checked the xtra2.bin from my address above against the one from your file. They don't match either, so the xtra1 subdomain is actually providing a different resource. Same with the xtra2 (checked), and presumably, xtra3 subdomains.
What do we know about these files? Why is the xtra2.bin specifically listed on our conf? Could be a regional thing.
There is also an xtra4 subdomain with a bin file for download, but no 5, which matches up with the 5 available entries in faster GPS.
Click to expand...

That's something I've been curious about as well, it has taken a little longer to get a lock with only the one xtra server, so it could very well be that each of the xtra servers provide different agps data for us, depending on locale?
 
jfuginay said:
How long did you give it before giving up? My very first lock took a very long time, at least 5 min. But subsequent locks are a lot faster, and the precision improved from within 30-40 feet to within 20-30 feet.

That's something I've been curious about as well, it has taken a little longer to get a lock with only the one xtra server, so it could very well be that each of the xtra servers provide different agps data for us, depending on locale?
Click to expand...
It would eventually lock, but it was unstable, and it took a long time every time. I also had to have direct view of the sky at least through a window. It just works better with LPP=1 and GLONASS=0x4 for me.

The only thing I don't get is that there is an xtra.bin and xtra2.bin available for download. What's the difference? Each server has one of each, so do we need all five, or is there a bin and 2.bin pair we need based on locale? Or is it something else entirely? Unfortunately I haven't been able to find any info on these files other than their existence and that they do provide AGPS data.

I guess you could test by using a pair from one server at a time and see how quickly it locks.
 
GPS seems to have just died. Can't get a lock, won't even pick up a satellite. I recently wiped the phone, reinstalled zv3, and OTA updated before rerooting. I did not do anything with the GPS until I was all updated. I tried my last conf that I posted, your current version, and I've been making adjustments to it since with absolutely no response. Do you happen to have the stock conf file sitting around? I don't think I uninstalled anything that would mess up the GPS.
Where is the error log located?

Update: left GPS test up and eventually got a lock with my conf file, but it kept going in and out. Could've been the area, but I would think signal would be good around Grand Rapids MI.

More testing later.
 
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bg4m3r said:
GPS seems to have just died. Can't get a lock, won't even pick up a satellite. I recently wiped the phone, reinstalled zv3, and OTA updated before rerooting. I did not do anything with the GPS until I was all updated. I tried my last conf that I posted, your current version, and I've been making adjustments to it since with absolutely no response. Do you happen to have the stock conf file sitting around? I don't think I uninstalled anything that would mess up the GPS.
Where is the error log located?

Update: left GPS test up and eventually got a lock with my conf file, but it kept going in and out. Could've been the area, but I would think signal would be good around Grand Rapids MI.

More testing later.
Click to expand...

I think I have the stock gps.conf somewhere, I'll try to get it up here soon, but if your phone is anything like mine it will likely only make it worse. I noticed recently as well that my gps wasn't keeping lock, especially when playing Ingress, even occasionally with Gmaps. After an extreme bout of patience, my gps locked, but it was seriously after at least 20 to 30 minutes of letting it talk to satellites.
 
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