Re: Web page updates following recent discussions

[Gary E. Miller]

Yo David!

On Wed, 20 Jan 2021 11:35:52 +0000
David Taylor <gm8arv@yahoo.co.uk> wrote:

> On 19/01/2021 19:31, Gary E. Miller wrote:
> > There has been lots of earlier discussion on this with ntpviz
> > providing read data.  I suggest you setup ntpviz and collect real
> > data.
> > 
> > RGDS
> > GARY  
> 
> Thanks for that pointer, Gary.  I've been collecting NTP data for
> some years now, and I'm basically happy with this.

Care to sahre your data?

> - to disable the OS from setting the RTC - I gather there's an
> 11-minute time controlling this

That is certainly not the way Uputronics says to do it.  That breaks
the RTC disciplining.  The preferred method is to let it free run
and store the drift.  See "man hwclock".

> - to have the RTC cause an interrupt (say every minute) and record
> the PPS-disciplined system time when that happens.

I don't see how the Uputrnics can do that.

> There's no suggestion of using the RTC to control system time other
> than at initial power-up.  It's more an exercise to measure the RTC
> itself.

If you just want ntpd to measure, not use, the RTC, then set it "noselect".
Otherewise ntpd will eventually use it4.

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

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

pgp1iwavXLgvY.pgp
Description: OpenPGP digital signature