[ntp:questions] Visual clock display?

Ralph Aichinger ralph at pangea.at
Sat Aug 25 19:08:10 UTC 2012

Chris Albertson <albertson.chris at gmail.com> wrote:
> The limit of accuracy of the visual clock is the refresh rate of the
> monitor.   One the old CRT monitors there was a vertical sync that ran at
> about 60 to 100 Hz.  I think LCDs have something like this too.   You can
> do better than 100 mSec using your method.  In fact it can approach the
> vertical sync limit.

100ms is just fine for me, I think. I don't know how much
the console driver or a GUI layer adds.

> The system can do better timing but the 100 Hz (or so) screen refresh is
> the limit.  Actully you eyes can't see a change that is faster than about
> maybe about 30 mSec.  But you CAN see 100 mSec ticks.  Run your update loop
> at 100Hz and you will be fine

Is there an "official" program that displays the time of the ntpd
process? Or is one supposed to get time for uses like this from the
system clock? Not that I think it makes a difference with 100ms 
accuracy, but as a matter of principle it would interest me.


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