On Wed, Jul 10, 2019 at 8:00 PM folkert wrote:
>
> > Folkert van Heusden has a driver for NTP which includes PPS output:
> > https://vanheusden.com/time/rpi_gpio_ntp/
> > Perhaps this might help?
>
> Indeed I did! :-)
>
> But please note that the jitter is high, iirc around 18ms.
> Personally I
> > Folkert van Heusden has a driver for NTP which includes PPS output:
> > https://vanheusden.com/time/rpi_gpio_ntp/
> > Perhaps this might help?
>
> Indeed I did! :-)
>
> But please note that the jitter is high, iirc around 18ms.
> Personally I would use
> Folkert van Heusden has a driver for NTP which includes PPS output:
> https://vanheusden.com/time/rpi_gpio_ntp/
> Perhaps this might help?
Indeed I did! :-)
But please note that the jitter is high, iirc around 18ms.
Personally I would use https://github.com/mlichvar/pps-gpio-poll.git and
then
I wrote:
> I'm guessing there are some time nuts here who might be able
> to give me some pointers.
And there were! Thanks for the suggestions & comments.
Dana Whitlow wrote:
> in the absence of a PPS or other electrical output from your
> "computer", what is the nature of the time "output"?
s...@eskimo.com said:
> My specific question concerns the case that one of the boxes is a computer,
> for example, a Linux box with time kept using ntpd or chrony (perhaps also
> listening to a PPS signal coming in on a serial port). But I've never seen a
> computer with a PPS *output*.
There
From: Steve Summit
[]
My specific question concerns the case that one of the boxes is
a computer, for example, a Linux box with time kept using ntpd
or chrony (perhaps also listening to a PPS signal coming in on a
serial port). But I've never seen a computer with a PPS *output*.
Several comments:
What level of accuracy do you mean by "synchronized"?
Plotting a lightly loaded Linux box, which is extracting time from the
network via timesyncd, against a GPS 1PPS signal, I observe typical time
excursions within +/- 10 ms, and extreme excursions over a 24 hour period
of up
Steve,
I'm curious: in the absence of a PPS or other electrical output from your
"computer",
what is the nature of the time "output "? If it's just visual via a
display, why not view
the light output of the seconds digit with a photocell. Most of the
transitions should
produce an
This is a different sort of question than what seems to be
discussed here usually, and I apologize if it's wholly off-topic,
but I'm guessing there are some time nuts here who might be able
to give me some pointers.
If I have two boxes with clocks that are supposed to be perfectly
synchronized,
