Re: [gpsd-dev] RaspbPi HOWTO

[Gary E. Miller]

Yo Frank!

On Thu, 5 May 2016 08:59:41 -0400
Frank <address@hidden> wrote:

> > That by itself makes it a questionable choice for a time
> > server. :-)  
> 
> I mentioned that in the another discussion, when I mentioned using a
> USB puck GPS instead of fighting with HATs & GPIO.  I’ll ask it again
> here - the issue/performance with polling on a USB puck GPS (limited
> to USB polling speed), does that same issue/concern apply because the
> Ethernet is on the USB bus?

I have never seen a USB GPS w/ PPS be the limiting factor, always the
NTP over the ethernet.  I'll do a test today on a Pi2 to see if that
continues to be true.

That said, PTP over GigE is clearly better than a USB GPS w/ PPS.
Sometimes approaching a few microSec jitter/wander/dispersion.

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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