Re: [gpsd-users] GPSd NMEA only parsing GGA, not VTG

[Chris Kuethe]

There is no problem - see driver_nmea0183.c:1105.

In the general case where you want to see all packets produced by a
receiver, not just the ones that gpsd has a handler for, you need to
use super-raw mode. Have a look at what gpspipe does when you run it
with the -R flag.

On Mon, Apr 23, 2012 at 20:07, Thomas Peel <address@hidden> wrote:
> Hello,
>
> I'm requesting some help as I've been struggling with the following issue for 
> several days without finding any explanation to what's happening.
>
> I would like to use GPSd on a research vessel to make ship's position 
> available to everyone onboard. Therefore, I need to parse generic NMEA GGA 
> and VTG sentences. Here is what the sentences look like from the serial port 
> GPSd is listening to :
>
> $GPGGA,030013.00,1401.83717,N,13008.84236,W,1,06,01.1,000.000,M,0.0,M,0.0,0000*58
> $GPVTG,126.48,T,069.57,M,000.05,N,000.10,K,D*26
>
> Unfortunately only GGA is parsed. VTG seems to be ignored, though the syntax 
> looks correct. Here is a dump of GPSd running with debug level 8 :
>
> gpsd:IO: <= GPS: 
> $GPGGA,030401.00,1401.83545,N,13008.84126,W,1,06,01.1,000.000,M,0.0,M,0.0,0000*58
> gpsd:DATA: GPGGA: registers fractional time 30401.00
> gpsd:WARN: can't use GGA time until after ZDA or RMC has supplied a year.
> gpsd:DATA: GGA: hhmmss=030401.00 lat=14.03 lon=-130.15 alt=0.00 mode=3 
> status=1
> gpsd:PROG: GPGGA sentence timestamped 30401.00.
> gpsd:PROG: GPGGA starts a reporting cycle.
> gpsd:PROG: GPGGA ends a reporting cycle.
> gpsd:DATA: packet from /dev/ttyS0 with 
> {ONLINE|LATLON|ALTITUDE|STATUS|MODE|PACKET|CLEAR|REPORT}
> gpsd:IO: <= GPS: $GPVTG,209.25,T,070.17,M,000.10,N,000.18,K,D*23
> gpsd:DATA: packet from /dev/ttyS0 with {ONLINE|PACKET}
>
> Testing other sentences reports that GGA, RMC and ZDA only are parsed. All 
> the other sentences are ignored like VTG.
>
> Could you please give me some clues on where this problem could come from?
> Many thanks in advance,
>
> Thomas Peel
>
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>



-- 
GDB has a 'break' feature; why doesn't it have 'fix' too?