Yo Steve!
On Tue, 1 Dec 2020 11:54:04 -0600
Steve Bourland <
sbourland@swri.org> wrote:
> > Yes, get a fix first. You can use cgps to know when ou have a fix.
> So from cgps on the server today:
Only 5 sats used, and they have marginal SNR. On the ragged edge of a 3D
fix.
> (Sorry, I did some whitespace editing in hopes that comes through
> well on the other end)
Good enough. Adding as text attachment avoids most email issues.
> So that looks to me like I have a fix or am I reading it incorrectly?
Yes, 3D fix with DGPS. So gpsd should be sending PPS.
> % ntpq -pn
> remote refid st t when poll reach delay
> offset jitter
> ===============================================================================
> xSHM(0) .NMEA. 0 l - 16 377 0.0000 -173.812 23.2042
> SHM(1) .PPS. 0 l - 16 0 0.0000
But no PPS. You also do not have enough other chimers. Hard to
vote with only 2 voters.
> # ppstest /dev/pps0
> trying PPS source "/dev/pps0"
> found PPS source "/dev/pps0"
> ok, found 1 source(s), now start fetching data...
> source 0 - assert 1606844580.999843801, sequence: 87291 - clear
> 1606844581.099837210, sequence: 87291
That is good. What is your gpsd command line? See it this way:
# pstree -paul | fgrep gpsd
> So is this a case where gpsd is feeding the kernel pps but not ntp's
> shared memory?
Uh, you have if backwards. The kernel feeds PPS to gpsd. Then gpsd
uses a SHM to eed it to ntpd.
> The shared memory looks "correct" to me as best I can tell:
Yeah, but what is in the SHM?
What does ntpshmmon show you? Somthing like this:
# ntpshmmon
ntpshmmon: version 3.21.1~dev
# Name Seen@ Clock Real L Prc
sam NTP0 1606845882.050103448 1606845881.573978673 1606845867.999628191 0 -20
sam NTP1 1606845882.050114664 1606845881.462974487 1606845881.462907608 0 -30
sam NTP1 1606845882.463990992 1606845882.463088891 1606845882.463021608 0 -30
> Although with the perms at 600 for segments 1 and 2, could that be
> the issue?
You need to be running gpsd and ntpd as root, of course.
> I would think if that were the case the NMEA would have
> the same problem?
Yes.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
gem@rellim.com Tel:+1 541 382 8588
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