Depending on the gps, there can be a dead-reckoning mode that will
extrapolate things for some time (often settable).  The pps may or may not
follow.
On May 2, 2012 5:19 PM, "Hal Murray" <hmurray@megapathdsl.net> wrote:

>
> gem@rellim.com said:
> > Looking for that check in the gpsd code, I do not see it in the PPS path
> or
> > in the NMEA path.  I wonder when that disappeared?  That may explain some
> > things...  I'll go add that back in now.
>
> I think there is another piece of fine print in that area.  I'm not sure
> where I saw it, probably one of the Garmin docs.
>
> The idea is that you can't trust the first few seconds of data when it
> switches from not-enough satellites to enough.  I've seen it give bogus
> position (way off) marked as valid.  I think they all happened right after
> recovering from not-enough-satellites.
>
> I'll scan log files if anybody wants examples.
>
>
> --
> These are my opinions, not necessarily my employer's.  I hate spam.
>
>
>
>