Re: [gpsd-dev] ✘xgps

[Gary E. Miller]

Yo Eric!

On Wed, 30 Mar 2016 12:08:37 -0400
"Eric S. Raymond" <address@hidden> wrote:

> Gary E. Miller <address@hidden>:
> > > 3. I'm not sure I understand the Baidu problem.  Yeah it's weird
> > > that the BDGSA sentence is claiming 3D fix with one sat, but
> > > maybe the firmware is mixing in pseudoranges from the GNSS birds
> > > as well.  I see lots of sats in the skyview, so what is the
> > > actual bug here?  
> > 
> > The Skytraq NMEA is reporting that is it using several GNSS and one
> > Baidu bird for the 3D fix.  But the gpsd json output only shows the
> > one baidu bird as used. Looks like the GPGSA data is getting
> > overwritten by the BDGSA data.  
> 
> OK, I had forgotten how this works.  That will happen, but only on the
> first cycle.  In your sample, the first cycle looks like this:

I made the same mistake as you.  Notice I said GSA, and your example is
GSV!

> $GPGSV,4,1,13,23,66,310,29,03,65,186,34,26,43,081,27,16,41,124,39*7E
     ^^^

I am talking about GSA, not GSV.

> GSVs are reported once per five cycles, so the the xgps sat display
> will straighten itself out ten seconds in.

Yes, GSV gets handled, but the GSA problem persists forever.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        address@hidden  Tel:+1 541 382 8588

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