Re: CLKADJ?

"James M. Prange" <jmprange@xxxxxxxx> schrieb

Hey, is anyone in favour of building a GPS navigational system
into a calculator?

I have heard about, that it is possible. I have
a PPC with naviation system, which reads the time from GPS.
Ok, you might use GPX for setting the time, but you need
an extra device (the GPX-receiver (mouse)).
For time keeping it would be realy nice to apply a
program, which is correcting the time, based on former
settings (calibration). I do not care, if the setting/calibration is
done manualy or with GPS.

GPS is not that accurate.
Today, I have measured 2.2 s difference to my radio clock,
and my radio clock shows exactly the time form the
ntp-server time.nist.gov.

....
Temperature compensation would be desirable; our calculators don't
always enjoy as stable a temperature as a watch or clock typically
would.

The real time clock of the hp49g+ seem to be not that sensitive to
temperature (this is my impression only ;-), but the
8129 Hz timer of the HP 48/9G is.
I think. Is it possible to correct with the frequence of the CPU,
which is temperature sensitive as well?
First let us force to correct the buggy 49g+ time management.

How close is close enough, and how much are we willing to pay to
have our calculators also function as precision time pieces?

HP 49G is very accurate with a time keeper, better than a
Casio or Seiko watch, and for some watches the 49G is
eaven cheaper (ok, temerature and exsessive use of it may make it
wors).

A basic question with the ARM processor is what is being used as
the time base for the 49g+? Does the emulated Saturn have access
to a 32768HZ (or any multiple of 8192Hz) signal unaffected by ARM
processor speed modes?

Ja, I would like now about the "secrets", like you.

Best regards
Heiko


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