Re: [External] Re: Time precision in gps_fix_t

[Gary E. Miller]

Yo Greg!

On Wed, 22 Jan 2020 15:34:51 -0500
Greg Troxel <address@hidden> wrote:

> > Multiple TPV with the same time stamp is not unusual.  Care to
> > share your raw dumps?  
> 
> Sorry, I don't have raw dumps available to share.    I will if I can
> generate some.

No rush.  You are not the guy with the problems.

> This was a clear pattern of two TPV lines with the same timestamp, for
> every second.

As I said, not unusual.  And not useful if not from git head code.

> > Regardless, getting time to 100 micro seconds from the serial data
> > is unlikely by at least 2 orders of magnitude.  
> 
> I am not talking about time sync.   If one has > 1 Hz positions, you
> want to be able to have those time tagged correctly so you can
> interpolate based on your (synchronized) system clock to get
> within-second position estimates.

Of course, but the OP was concerned with time sync.

> This is a very noticable issue
> with lots of nav programs on android (probably more about not
> extrapolating the pointer, vs multiple positions per s).

Luckily, or unluckily, android is not running gpsd.

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

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