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Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared mem
From: |
Gary E. Miller |
Subject: |
Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver |
Date: |
Wed, 10 Aug 2016 11:27:57 -0700 |
Yo Jon!
On Wed, 10 Aug 2016 02:11:26 -0500
"Jon Brase" <address@hidden> wrote:
> > Have you looked at the RasPi HOWTO?
>
> Which RasPi HOWTO are you referring to.
Well, the one that gpsd and ntpsec have been working on:
http://www.catb.org/esr/faqs/stratum-1-microserver-howto/
Plus more info in the gpsd howtos in the tar ball:
gpsd-time-service-howto.txt
INSTALL
> Different ones recommend different
> setups.
It is Unix, many way to skin the cat.
> Anything that recommended using 28.0 and 28.1 has come to
> grief trying to get GPSD to pick up PPS on the Pi
Well, that is just wrong. Driver 28 is the best way.
> Using 28.0 and
> 22.0 seems to work best of everything I've tried
It has weird failure modes. Get some day/week/month graphs and you'll see.
> > Which makes it real easy to get the PPS on the wrong second. Or
> > worse, following PPS when the PPS is not valid.
>
> But that's the point of the offset fudge on the coarse data, right?
Half way. Driver 22 has no way of knowing when the PPS is invalid. It
will follow a bad PPS into the weeds.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
address@hidden Tel:+1 541 382 8588
pgpymzM2CCnKc.pgp
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- [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/09
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/09
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Gary E. Miller, 2016/08/09
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/10
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver,
Gary E. Miller <=
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/16
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Gary E. Miller, 2016/08/16
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/17
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Jon Brase, 2016/08/17
- Re: [gpsd-users] Large ntp.conf time1 offset needed with GPSD shared memory driver, Gary E. Miller, 2016/08/17