Re: [gpsd-users] Unexpected behavior

[Gary E. Miller]

Yo Nick!

On Fri, 15 Sep 2017 09:52:19 -0700
"Nick Burkitt" <address@hidden> wrote:

>                 <M>      Kernel timer client (Testing client, use for debug)
>                 <M>      PPS line discipline
>                 <M>      PPS client using GPIO

I suggest you compile them into the kernel, instead of
as modules.  But not a big deal.

> The expected duration is, of course, 100 ms, and every second KPPS
> cycle report matches that expectation. But in between the expected
> duration reports are reports claiming a 900 ms duration,


Well, 100ms + 900ms is 1 second.  That is 100% expected and proper.

> and then the
> TIOCMIWAIT warnings, which suggest that GPSD is using user-space PPS
> instead of KPPS.

Of course, gpsd auto configures.  Not a problem.

> While GPSD is running, I can cat the pps assert and clear sysfs
> files, which seem to return reasonable values.

Why bother?  The gpsd debug output shows that, and more.

> My question, then, is - does it appear that KPPS and/or GPSD are
> functioning incorrectly (or have been incorrectly configured)? 

Looks perfect to me.  But the way to really know is to feed NTPsec
from gpsd and see what ntpmon thinks of your data.

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

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