Re: 2 separate positions pass through gpsd

[Filip Kubicz]

Hi Gary!

> Every other DR receiver does that for you.  Quectel should not make the
client do that.

I'm aware of it - their team is working on a fix for this.

> $PQTMINS, $PQTMIMU and $PQTGPS do not return time!  So no way to include
thme in a TPV report.  There may be a way to showhorn this mess into an
ATT report.

This hurts, but the time must come from $GNRMC or $GNGNS -
unfortunately you cannot base only on the $PQTMINS. Looks like gpsd is
merging the time into TPV coming after each $PQTMINS pretty well.

> We can add new variables in gps_fix_t if needed.  But if you are getting
rounding errors on doubles, you got big problems.

The rounding was coming from gpsd_json.c: it was putting these doubles
into json with just 1 decimal place (for the wing angle variables).
For now, I worked it around by putting 9 decimal places, the same as lat/lon.
I'm happy with this solution - until a FW fix arrives.

> Go ahead an make Merge Request to gpsd with your code.  It will need a
lot of work.  Easier for me to add and track comments in the MR process.
If nothing else just getting the decodes to the log output would be
helpful.

Sure - for the $PQTMINS. The $PQTMGPS is a temporary quick fix and I
would not include this into gpsd. As soon as Quectel releases a new
firmware, it will not be needed.

Kind regards,
Filip

On Fri, Oct 14, 2022 at 1:42 AM Gary E. Miller <gem@rellim.com> wrote:
>
> Yo Filip!
>
> On Thu, 13 Oct 2022 12:11:45 +0200
> Filip Kubicz <filip.kubicz@tier.app> wrote:
>
> > Got any documentation on this mess?  I can do nothing until I have
> > doc.
>
> I found some doc here:
>
> https://www.quectel.com/wp-content/uploads/2021/06/Quectel_LC29D_DRRTK0_Application_Note_V1.0.pdf
>
> This is worse than I thought.  Even for Quectel.
>
> $PQTMINS, $PQTMIMU and $PQTGPS do not return time!  So no way to include
> thme in a TPV report.  There may be a way to showhorn this mess into an
> ATT report.
>
> Go ahead an make Merge Request to gpsd with your code.  It will need a
> lot of work.  Easier for me to add and track comments in the MR process.
> If nothing else just getting the decodes to the log output would be
> helpful.
>
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>         gem@rellim.com  Tel:+1 541 382 8588
>
>             Veritas liberabit vos. -- Quid est veritas?
>     "If you can't measure it, you can't improve it." - Lord Kelvin