[ntp:questions] Reading the RTC

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Tue Sep 25 20:20:21 UTC 2007


>Unless I missed something, the RTC raises the IRQ when the fraction of a
>second is 0.5 NOT when it is 0.
>
>Or is something perhaps delaying the IRQ by 500 ms every time?
>
>In other words, when I receive the IRQ, and the RTC tells me the date,
>it is, in fact, 500 ms later than this date?

It sounds like you are interrupting on the wrong edge of the
signal.  Can you easily change the interrupt setup code
to try the other edge?

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