Thread: Unable to log GPS data

Could you look at the output of cgps and see what it claims the fix is? OBDGPSLogger doesn't log GPS until it has at least a 2D fix; just seeing some satellites in XGPS doesn't necessarily mean that it actually has a fix.

Could you paste the actual output of obdgpslogger? obdgpslogger relies on gpsd, so you need to be sure that gpsd is up and running [with a gps receiver attached] *before* obdgpslogger starts, for it to work.

Could you also post a short logfile showing the problem? The logfile is actually a sqlite database, so I'd be opening it to see if there are at least rows in the gps table; how are you looking to see if the gps is being created? It's concievable that there's a bug that causes obd2kml or obd2csv to not show gps co-ordinates, even though they're in the log

Thanks,
Gary (-;

I haven't had time yet to get back into the car to test this out, but I remember having a 3d gps fix on it when I checked out xgps.

gpsd was running and obdgpslogger detected it and indicated it will also log the gps data.

I checked the db by running select * from gps; and that returned 0 rows.

then tried .schema gps and got this

CREATE TABLE gps (lat REAL, lon REAL, alt REAL, time REAL, trip INTEGER);
CREATE INDEX IDX_GPSTIME ON gps (time);

I'll try to get back in the car to get the actual output of all involved programs by today or tomorrow.

ps. attached the log

Thanks!

Ok I just got to get another run, here's what I got


~/obd/02122010 $ obdgpslogger -b 38400 -s /dev/obd -a 10
Opening serial port /dev/obd, this can take a while
Successfully connected to serial port. Will log obd data
Successfully connected to gpsd. Will log gps data
Creating a new trip


It is a new directory and is completely empty before I ran the command.
I also ran cgps in another window before running obdgpslogger, it indicated a 3d fix. I then closed cgps, ran obdgpslogger and drove for around 30 secs to 1 minute then stopped. I once again started cpgs to make sure the fix is still active, while keeping obdgpslogger running.

When I checked the tables afterwards, same thing: a populated obd table and completely empty gps table.

Is there any checking on the gps data to filter out probable garbage data?

OBDGPSLogger usually announces the first time it sees a 3d fix:

Code:

if(0 == have_gps_lock) {
  fprintf(stderr,"GPS acquisition complete\n");
  have_gps_lock = 1;
}

That it's not seeing that means there's some kind of disconnect - perhaps there's a problem with versions of libraries, where obdgpslogger is linked against one library, but you're using a different version of gpsd? You said you're using gentoo and have built it multiple times - can you verify which libgps it's linked against? [use ldd]

What's the version of gpsd in your path? Just run gpsd --version and see what it says, and compare that to the libgps that obdgpslogger is linked against?

I need to build gpsd2.90 myself, I haven't actually tried my code yet; I just followed the documentation on the transition to the new API. It's possible there's an artifact in there somewhere.

Thanks,
Gary (-;

Code:

# gpsd -V
gpsd 2.32

Code:

ldd obdgpslogger 
	linux-gate.so.1 =>  (0xb80b9000)
	libpthread.so.0 => /lib/libpthread.so.0 (0xb8078000)
	libdl.so.2 => /lib/libdl.so.2 (0xb8074000)
	libgps.so.15 => /usr/lib/libgps.so.15 (0xb8055000)
	libdbus-1.so.3 => /usr/lib/libdbus-1.so.3 (0xb801d000)
	libc.so.6 => /lib/libc.so.6 (0xb7ed5000)
	/lib/ld-linux.so.2 (0xb80ba000)
	libnsl.so.1 => /lib/libnsl.so.1 (0xb7ebe000)
	libstdc++.so.6 => /usr/lib/gcc/i686-pc-linux-gnu/4.3.4/libstdc++.so.6 (0xb7dd1000)
	libm.so.6 => /lib/libm.so.6 (0xb7dab000)
	libgcc_s.so.1 => /usr/lib/gcc/i686-pc-linux-gnu/4.3.4/libgcc_s.so.1 (0xb7d9d000)

I never got around to learning how the numbers for the libraries are for, but when I built gpsd 2.90, there was no libgps.so.15, there was only libgps.so.19 . I'll try removing gpsd and reinstalling later, then recompile obdgpslogger.

I think I missed something you're asking for.. is there anything else?

No, that's good, but it did occur to me; could you please run ldd against xgps and/or cgps and see what that responds?

Thanks,
Gary (-;

Code:

ldd cgps | grep gps
	libgps.so.15 => /usr/lib/libgps.so.15 (0xb7e07000)

Code:

ldd xgps | grep gps
	libgps.so.15 => /usr/lib/libgps.so.15 (0xb79cf000)

I'll try to get more debug info on this during the weekend, as well as check out the code for obdgpslogger. What version of gpsd are you using, how about OS?

Thanks

FIXED

I unmerged(uninstalled) gpsd completely then emerged it again. I guess there were some garbage files left when I last tried that.

Running gpsd 2.32 now and obdgpslogger revision 386.

Yay! Glad to know it's working!

Gary (-;