Locus Map - forum

Support => Troubles & Questions => Topic started by: stebu on July 23, 2011, 10:12:29

Title: No NMEA data
Post by: stebu on July 23, 2011, 10:12:29
None of the NMEA settings "always" or "when recording on" produces any NMEA data to the SD card data/NMEA directory.
(Locus 1.9.4, Android 2.2, ZTE Blade)

I would have liked to check the effects of an external GPS antenna. If the NMEA data would work for me, would there be a sentence that provides the satellites signal strength (GSV)?

Otherwise this function is not important for me.
Title: Re: No NMEA data
Post by: auric on July 25, 2011, 09:52:19
Do you have any error messages in /sdcard/Locus/logs/ around that time?
On my DHD, both "Always" and "While recording" (the latter only while recording, of course) produces NMEA files in the given folder.

It is however saved in the folder /sdcard/Locus/data/nmea (notice the lowercase). Is your folder lowercase as well? And if so, is that folder writable? Maybe you want to remove it and let Locus recreate it (just guessing)
Title: Re: No NMEA data
Post by: stebu on July 25, 2011, 12:22:05
Thanks for the response! But unfortunately it didn't help. The folder was exactly as you told. Anyhow, I deleted it and Locus created it back. But no data items :(
Title: Re: No NMEA data
Post by: Menion on July 25, 2011, 16:47:18
hmm interesting. I think this should be some 1. problem in ROM (are you using custom?) or GPS chip in your phone do not offer NMEA data to system. Interesting should be to try this with BT GPS on your phone, because I use same system for storing NMEA messages for internal or BT GPS. And yes, if sentences works correctly, there should be GSV. But it's not one of most required so I cannot tell for sure!
Title: Re: No NMEA data
Post by: stebu on July 25, 2011, 17:59:46
My ROM is directly off-the-shelf.
I just wonder where Locus gets the satellite data for the GPS-screen? Is there some other possibility than NMEA GSV-sentence?
Title: Re: No NMEA data
Post by: Menion on July 25, 2011, 18:16:22
normal behavior of getting GPS data is by some system function that allow this. I can anyway register something called "listener" that allow to receive NMEA messages that goes from GPS. So If you do not enable this NMEA recording, listener is not active, so I have no idea what NMEA sentences are coming from GPS to system, I only receive computed data.

any other possibility ... don't know. Did anyone know about any other program that allow record NMEA message from internal GPS?
Title: Re: No NMEA data
Post by: stebu on July 25, 2011, 20:25:33
I just checked and found an app:
GPS Nmea Monitor (//https://market.android.com/details?id=com.chartcross.gpsmonitor&feature=search_result)
"This app displays raw NMEA data coming from the GPS chip. Can be used to check the GPS on your phone.
Please do not give bad ratings if the app does not display any NMEA, The NMEA API does not work on some phones."

I'll shut up about this, I can live without it.
Title: Re: No NMEA data
Post by: Menion on July 25, 2011, 21:41:57
hmm this is what I expect ... so I'm sorry for you. But if you're just interested in accuracy number, this should be same as on GPS screen.
Title: AW: No NMEA data
Post by: druki on March 10, 2012, 14:47:46
Hello,
there seem to be several devices (mobile phones) that doesn't support NMEA output from their built in GPS. Often the hardware could handle it, but the software (ROM) of the phone manufacturer doesn't use it.
Unfortunately my Motorola Defy+ (MB625) is one of this.
After trying to get NMEA data with other apps ("NMEA Recorder" and "Simple NMEA Monitor" - both as free available), I found this in my research:

http://community.developer.motorola.com ... td-p/14374 (http://community.developer.motorola.com/t5/Android-App-Development-for/NMEA-Support-on-Defy/td-p/14374)

http://www.kowoma.de/gpsforum/viewtopic.php?f=3&t=3138 (http://www.kowoma.de/gpsforum/viewtopic.php?f=3&t=3138)
(at the end some interesting informations about the GPS chip in the Defy)

So sadly I have no possibility with my internal GPS yet. Maybe I give it a try with my bluetooth GPS receivers. Or I pray for motorola to activate this in an update.
Title: Re: No NMEA data
Post by: tommi on March 10, 2012, 17:23:03
druki, I think Locus has a solution for this problem.

Please check the latest comments in
https://getsatisfaction.com/locus/topic ... n_oruxmaps (https://getsatisfaction.com/locus/topics/gps_altitude_correction_using_nmea_like_in_oruxmaps)
Title: Re: No NMEA data
Post by: druki on March 10, 2012, 22:26:35
Hi tommi62, thanks for the link.
There they discuss about altitude correction and believe they get this information from NMEA (although it´s not proved that the altitude information is comming from NMEA). IMHO, in some devices, the altitude is given from internal GPS, but not by NMEA.
I played arround with internal GPS (with 3 different Apps and Locus) and bluetooth GPS hardware (Jentro BT-8), even with a bluetooth GPS-App:
With external GPS, I can record NMEA, with internal GPS of Defy+: no way
:-(
Title: Re: No NMEA data
Post by: tommi on March 11, 2012, 08:21:50
Hi druki,
seems my link was a misunderstanding. I thought you are just interested in acceptable accuracy of altitude information which is the end of the long story from the link. But now as I first time had a look what NMEA actually means I understand that it is much more.
Title: Re: No NMEA data
Post by: Menion on March 11, 2012, 11:21:25
Druki, I was investigating this also when i was testing "altitude correction" feature and result is same as yours. Some devices do not have possiblity to show NMEA messages. Don't know why is this disabled, but it is ... anyway with external BT it have to work because there are GPS data extracted from these messages directly (compare to internal GPS where NMEA messages aren't needed)