[ntp:questions] Slightly OT: Looking for good GPS PCI time sources

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Sat Jul 7 20:10:55 UTC 2007

>One consideration might be whether the cards in question allow readout
>of the time as a single atomic operation -- if they don't, one can't
>(for example) read the time without worrying about locking...

You don't need a lock.  The standard trick is to read the
high-bits, low-bits, then high-bits again.  Then compare the
two high-bits readings.  If they are the same you are done.
If not, it overflowed from the low to high bits between
readings.  Try again.

These are my opinions, not necessarily my employer's.  I hate spam.

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