refclock 28 gone wacky on me

Gary E. Miller gem at
Fri Jun 10 00:27:51 UTC 2016

Yo Mike!

On Thu, 9 Jun 2016 20:19:19 -0400
Mike <bellyacres at> wrote:

> On 06/09/2016 07:20 PM, Gary E. Miller wrote:
> > Yo Mike!
> >
> > On Thu, 9 Jun 2016 18:21:32 -0400
> > Mike <bellyacres at> wrote:
> >  
> >> Is seeing NTP0 twice like this typical?  
> > I'm looking at the code, maybe a couple of things to double check.
> >
> > Can you send me, off list, the output of this command, about
> > 60 seconds worth should do it.  As long as is captures a few good
> > PPS pulses.
> >
> > 	# gpsd -nND 9 /dev/ttyXX |& fgrep PPS > text.log  
> I'll send it if you still want after this reply.  After I posted
> seeing NTP0 twice, stopped everything, issued ipcrm -a, restarted
> gpsd and now the output is normal again.  PPS is still off 1sec...

Well, so you still have the same bug, thus I still want the same
bug report.  UNless you do not want the bug fixed.

> As to the baud rate, I built this using clockmaker --build, which
> sets the baud to 9600 by default.

Clockmaker is not even released, much less widely tested.  9600 baud
is the default speed for the Adafruit and Uputronics HATs and as
we are still characterizing those we can not yet know if that is a good
speed for those yet.

We KNOW that 9600 is not fast enough for many GPS, or if the user
has enabled extra sentences.  it is only in the spirit of KISS that
we are even attempting 9600.

Turn off gpsd, cat the GPS serial output, and verify that the serial
stream consistently has a pause every second.

But I agree this is looking less likely given your double pulse issue.

So, to debug that, I need the output of:
	gpsd -nND 9 /dev/ttyXX |& fgrep PPS > gpsd.log

Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
	gem at  Tel:+1 541 382 8588
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