Pre ubiquitous internet with NTP - we ran special projects with Windows PCs -
but time keeping was always a problem - we would use one of our embedded
controls with line frequency time keeping - which is very accurate - the funny
thing when power went off we used the same Dallas Chip as on the
My Dad who taught Electrical Engineering told me that when parts are sold
in different quality grades (like resistors or in this case, crystals),
that the parts that meet the highest spec are sold for a high price, then
the next highest quality spec parts are sold for less, and so on. So your
On Wed, Sep 29, 2021 at 1:48 PM Poul-Henning Kamp wrote:
> Since these embedded chips generally are incredibly robust with
> respect to timing, the xtal on the BOM is the cheapest that will
> meet spec.
Crystals? We don't need no stinking crystals!
At least for the RTC. Chips like, e.g. the
Alec Teal writes:
> So you suspect/expect around the time frequency changes started
> happening, clocks became crap?
Well, it gets complicated fast there, but yes, that's pretty much
where the shit inescapably hit the fan.
Previous to that, most CPU's were clocked with a small PLL
Hi
If your wrist watch is holding 3 seconds per year without some sort of external
correction, that’s pretty amazing …. 10 seconds a month is doing well.
Bob
> On Sep 29, 2021, at 2:35 PM, Alec Teal wrote:
>
> Hi there,
>
> I have a question and I cannot think of anyone better to ask, for
I assume you're talking about the RTC chip that runs off the CMOS BIOS
memory settings battery, to keep time whether the computer is on or off.
These are as you suspect, typically cheap items that get the basic job
done. You may be able to find better grade ones. It also depends on
whether the
Alec,
I seem to perceive that PC clocks have gotten quite a bit better since
their early days. What do others think?
Dana
On Wed, Sep 29, 2021 at 3:10 PM Alec Teal
wrote:
> Hi there,
>
> I have a question and I cannot think of anyone better to ask, for a
> project we need to time some things
Alec Teal writes:
> My theory is that super cheap crappy quartz clocks are now used in
> things which can be reasonably expected to be online most of the time,
There are multiple answers to your question.
The funny one is: When they set fire to a prototype motherboard
at Intel
