[GPS/AGPS] REAL solution analysis thread (Jupiter Tweaks) - v006! - Froyo JI6

[Unhelpful]

Captivate? I've only seen agpsd in Vibrant dumps before, and it didn't seem to work on Captivate, even with the Vibrant gps libraries.

Sent from my SAMSUNG-SGH-I897 using XDA App

 

[jason531]

Thank you for this thread, CL, especially the "re-education" part. I had read about some of those concepts in various sources, but your summary is very readable, concise, and informative.

I concur with the theory that AGPS is a major cause of the problem. Mine only works acceptably in standalone mode. I also have seen the "driver reset" issue where I cannot get a lock, disable/enable the GPS, then get a lock within 5-10 seconds.

Please let me know if there is anything I can do to help, since the best Captivate support comes from XDA, not AT&T/Samsung. I have a Captivate running Cognition 2.1 (JH7) and also have access to my wife's Droid 2 (Froyo). Thanks again for working on this issue.

Edit: I mention the Droid 2 for comparative testing. Last night I was walking around running My Tracks simultaneously on both phones to see if both of the little blue circles included my known position.

 

[Asraiil]

Thank you for this thread, CL, especially the "re-education" part. I had read about some of those concepts in various sources, but your summary is very readable, concise, and informative.

I concur with the theory that AGPS is a major cause of the problem. Mine only works acceptably in standalone mode. I also have seen the "driver reset" issue where I cannot get a lock, disable/enable the GPS, then get a lock within 5-10 seconds.

Please let me know if there is anything I can do to help, since the best Captivate support comes from XDA, not AT&T/Samsung. I have a Captivate running Cognition 2.1 (JH7) and also have access to my wife's Droid 2 (Froyo). Thanks again for working on this issue.

Edit: I mention the Droid 2 for comparative testing. Last night I was walking around running My Tracks simultaneously on both phones to see if both of the little blue circles included my known position.

Ha! and here I thought I was the only one using my wife's phone (HTC Aria) for comparison testing! The price for using her phone is steep, as she keeps on poking me and asking why I have to use her phone if mine's so much better...

 

[NetCopAD]

Captivate? I've only seen agpsd in Vibrant dumps before, and it didn't seem to work on Captivate, even with the Vibrant gps libraries.

Sent from my SAMSUNG-SGH-I897 using XDA App

Wow! My bad! It's a Vibrant ROM. I've messed up with all this ROMs around LOL!

Guess I'll have to take a look again tomorrow after sleep

 

[sblees]

Ha! and here I thought I was the only one using my wife's phone (HTC Aria) for comparison testing! The price for using her phone is steep, as she keeps on poking me and asking why I have to use her phone if mine's so much better...

Lol... I have to keep my wife in the dark about my gps issues or else she will give me hell about why didn't I get the iphone.

Sent from my SAMSUNG-SGH-I897 using XDA App

 

[tazman171]

It seems to be more than just AGPS, will try with flight mode. Problem is, can't use google nav in that mode.

Sent from my Captivate/Voodoo 1.6 Ext 4

 

[phr00t]

Has anyone tried using the Blackberry's FrqPlan from the first post:

FrqPlan="FRQ_PLAN_26MHZ_2PPM_10MHZ_100PPB"

?

I've been doing some very small testing with it, but not enough to make any conclusions. I will test it on my way home (using Jupiter v002 and the above FrqPlan).

 

[no driver]

You could always load up your route in Navigate and then turn on flight mode. I did this a while back and after Navigate loaded up the map the GPS showed where I was even though I wasn't following the route Navigate had picked out for me. I'm not sure if it would load enough map data for a long drive but for my 25-30 minute commute home it had enough of the surrounding area to be usable without additional data past the initial loading of the map.

 

[whorider]

Does AT&T's own nav app work on this phone?

 

[foxbat121]

Does AT&T's own nav app work on this phone?

It can't perform miracles. If you GPS doesn't work well, the AT&T TeleNav will be affected as well.

 

[tmusall]

You could always load up your route in Navigate and then turn on flight mode. I did this a while back and after Navigate loaded up the map the GPS showed where I was even though I wasn't following the route Navigate had picked out for me. I'm not sure if it would load enough map data for a long drive but for my 25-30 minute commute home it had enough of the surrounding area to be usable without additional data past the initial loading of the map.

Or you can use MapDroyd from the market. It caches all maps offline then positions you using gps only. Should be good to use when testing in airplane mode.

 

[whorider]

It can't perform miracles. If you GPS doesn't work well, the AT&T TeleNav will be affected as well.

I was just curious, b/c AT&T sells that service for $9.99 a month. One might think that AT&T would be pushing sammie for a fix as well.

 

[Unhelpful]

I was just curious, b/c AT&T sells that service for $9.99 a month. One might think that AT&T would be pushing sammie for a fix as well.

Would somebody who would pay monthly for an inferior service even notice that the GPS doesn't work too well? I've used telenav on i617, and its flaws are many, but most annoying is the fixed distance at which it instructs you to turn. Often it does so 1-3 streets before the correct turn.

Sent from my SAMSUNG-SGH-I897 using XDA App

 

[MrBuddyCasino]

Out of frustration I got in the truck and drove a few miles north and suddenly 11 satellites popped up! Perfect tracking. Now even here at the house where I had only one satellite I've got 9-10. VERY WEIRD - all I did was go for a drive and it suddenly started working, and it's still working great.

This looks very much like a confirmation of the low-quality almanac data theory. This forum does not allow me to post an URL (le sigh), just google for "demystifying-gps-issues-samsung-galaxy-s-2.html", its the first result.

I use "GPS Status" to populate my almanac and ever since I did that (every few days), I get a fix in ~15 seconds and good static accuracy. Not sure I it helps with tracking accuracy (when moving), though.

 

[Joe1981AL]

CL, I know we are working on tracking issues here but on the quick fix topic try this and see if you see good results like I do.

edit your jupiter.xml file changing this, ltoFileName="/data/gps/lto.dat"

download an LTO from http://gllto.glpals.com/7day/latest/lto.dat
and place in /data/gps

I updated my jupiter.xml as above, loaded the lto.dat to location, went into lbstestmode and deleted gps data, turned on airplane mode and restarted the phone.

I started up GPS Test after reboot and had a solid lock of 10 sats in 45 seconds.


edit: If this does work, an app could be wrote to do the same thing quickGPS did on WM

 

[CLShortFuse]

I just got back from using v002 all day and it doesn't help with accuracy at all. AGPS isn't the problem. I've realized if you turn off the GPS and start it up again, you'll get a VERY accurate position. Something in the cache isn't right. We can force certain parts of the cache not to be used by these settings

ignore_osc="true"
ignore_rom_alm="true"
ignore_nav="true"
ignore_pos="true"
ignore_ram_alm="true"
ignore_time="true"

Which one(s) should we disable to test v003?

 

[Asraiil]

Ok, a couple of things:

First, I updated to Jupiter.002, went for a run, and my track was pretty accurate, it even got when I crossed to the other side of the road. (Thanks forum for not letting me put up pictures...

w w w dot flickr.com/photos/[email protected]/5031592190/

This area is pretty densely wooded, except for right where I began the track.

For a comparison, here's the beginning of my track from Work to Home, where it was way off even while sitting in a parking lot:

w w w dot flickr.com/photos/[email protected]/5031592218/

Now to my second thing:

I went to turn off the AGPS via the ADB shell commands:

adb shell
su
cd /dbdata/databases/com.android.providers.settings
sqlite3 settings.db
update secure set value="0" where name = "assisted_gps_enabled";
.quit
reboot

when I get to the sqlite3 settings.db command, I get the following error:

sqlite3: not found

I've tried various permutations of the command, and haven't been able to get it to come up at all. Any ideas?

 

[CLShortFuse]

Ok, a couple of things:

First, I updated to Jupiter.002, went for a run, and my track was pretty accurate, it even got when I crossed to the other side of the road. (Thanks forum for not letting me put up pictures...

w w w dot flickr.com/photos/[email protected]/5031592190/

This area is pretty densely wooded, except for right where I began the track.

For a comparison, here's the beginning of my track from Work to Home, where it was way off even while sitting in a parking lot:

w w w dot flickr.com/photos/[email protected]/5031592218/

Now to my second thing:

I went to turn off the AGPS via the ADB shell commands:

adb shell
su
cd /dbdata/databases/com.android.providers.settings
sqlite3 settings.db
update secure set value="0" where name = "assisted_gps_enabled";
.quit
reboot

when I get to the sqlite3 settings.db command, I get the following error:

sqlite3: not found

I've tried various permutations of the command, and haven't been able to get it to come up at all. Any ideas?

At this point, it's not worth it. Stick with v001

 

[foxbat121]

I tried turn on flight mode and the navigation accuracy didn't improve at all. So, at this moment I would say the driver in JH7 is still hosed. Samsung probably will take its sweet time to roll up any future GPS fix into Froyo update which we probably won't get until Nov at the earliest (Given that Europe will get it at the end of Oct.).

 

[Asraiil]

At this point, it's not worth it. Stick with v001

Ok,

Well I figured out how to use sqlite3 via the shell. I had to pull the settings.db, I hadn't actually pulled it before. I've got .002 in right now, and I've made the changes for disabling agps, but when I go to chown the file once it's back in it's place, I can't seem to do it and I get this error:

chown:  unknown user/group system:system

I did an ls -l to see the properties, and this is what I came up with:

# ls -l /dbdata/databases/com.android.providers.settings/settings.db
ls -l /dbdata/databases/com.android.providers.settings/settings.db
-rw-rw----    1 0        0            50176 Sep 28  2010 ←[0;0m/dbdata/databases/com.android.providers.settings/settings.db←[0m

anyone know how I can fix that? I'm running mostly stock, just using the voodoo fix kernel.