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" <
address@hidden> wrote:
address@hidden 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.