[time-nuts] Handy iPhone app
dave.martindale at gmail.com
Sun Jul 18 23:34:55 EDT 2010
I have an iPod Touch. It's an iPhone without the cellular radio, the
camera, the GPS, or the compass, but it runs most of the same applications.
Emerald Time works fine on it.
As far as I can tell, Apple refuses to acknowledge any timing precision
finer than minutes in their user interface. It displays the time on the top
of most windows, but only to 1 minute resolution. You can manually set the
date and time, but only to within 1 minute precision. The date and time
setting widget doesn't display seconds, and doesn't provide a way to reset
seconds to zero, or to temporarily stop the clock until the seconds are
synchronized with the correct time.
The Touch clearly doesn't get time from a cellular base station. It doesn't
seem to get its time set from the computer it syncs to either (at least not
from a Windows PC). My PC clock is set pretty accurately by a program
called "Nixie Clock" (it agrees with Emerald Time within 200 ms), while the
time on the Touch is 145 seconds off. Doing a sync with the PC does *not*
correct the time at all.
So I guess the only choice available to the Touch owner is manual time
setting. By looking at when the minutes roll over, or running Emerald time
and reading the error, you can get within 30 seconds of the correct time,
and that's all. The Touch internal clock isn't terribly accurate either.
Someday I should measure it to see how bad it is, but a quartz watch is
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