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IDMah

macrumors 6502
Original poster
May 13, 2011
317
11
Hey All.

I'm looking for thought on how to get a universal synchronized time.
Basically I need a reference that will be the same anywhere.

Is there a way to read the iphones clock but synced with Cupertino time? or something like it without the web access?

I want to co-ordinate devices with a time stamp.

thanks
Ian

ps. any help appreciated, or just pointing in right direction.. thanks !!!
 
I'm looking for thought on how to get a universal synchronized time.
Basically I need a reference that will be the same anywhere.

Is there a way to read the iphones clock but synced with Cupertino time? or something like it without the web access?

I want to co-ordinate devices with a time stamp.

Do you mean UTC -- ignoring timezone?

Or do you mean synchronized, such that you compensate for devices whose clocks were set manually or have drifted. If so, you need to consider how to send a calibration signal to the devices. Without net access this may not be straightforward ;)
 
iPhones already get their time from the cellular network. And I think iPods/iPad already use SNTP to get their time. The problem is solved, you don't have to solve it.
 
Yes a universal synchronized time.

ignore what the user's time is set to, ignore the time zone.

Basically a time stamp that will be the same no matter where you.
compensate for devices whose clocks were set manually or have drifted

It's looking like I need to have web access for this.. sigh ...

but I'll look into SNTP..

thanks
 
Exactly what problem are you trying to solve?

"Coordinate devices with a time stamp" is far too vague. It also fails to state how accurate the time stamp needs to be, nor explain why that accuracy is necessary.

You haven't said whether the devices are networked or not, either. I'm guessing, "not networked", otherwise you wouldn't be sighing about needing a network connection. So you have an unspecified number of non-networked devices that must still "coordinate" using timestamps, for some unspecified reason and with unspecified accuracy.

Unless you're doing navigation or observation of astronomical phenomena, I don't think a few seconds (or even a few minutes) inaccuracy is going to matter. But since you haven't explained what you're trying to do, that's just a guess.

Have you considered that GPS contains an accurate clock, and perhaps that information is available?


XY Problems
http://www.perlmonks.org/index.pl?node_id=542341
.. you want to do X, and you think Y is the best way of doing it.
.. Instead of asking about X, you ask about Y.

.. How do I use X to accomplish Y?
http://perl.plover.com/Questions3.html
 
not that accurate

Basically I need to know within seconds when an event takes place.
I'm not flying space ships. Just need some sore of reference to correlate one event with another, within a few seconds.

I'll look into gps timing.. and all the other suggestions.
but maybe I'll shelve the feature for 'future expansion.'

thanks
Ian
 
iPhones already get their time from the cellular network. And I think iPods/iPad already use SNTP to get their time. The problem is solved, you don't have to solve it.

Exactly and the way SNTP works the user would have be off network for a long time before the drift was enough to be worried about a "couple of seconds" of accuracy.
 
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