[ntp:questions] best gps receiver for time synchronization

David J Taylor david-taylor at blueyonder.neither-this-bit.nor-this.co.uk
Wed Mar 11 15:18:45 UTC 2009

Richard B. Gilbert wrote:
> David J Taylor wrote:
>> David Woolley wrote:
>> []
>>> You won't get millisecond accuracy on Windows.  Although the
>>> software clock can be disciplined to better than a millisecond,
>>> applications can only read to one tick, which is 10ms by default
>>> and 1ms with the fastest multi-media timers (which risks lost
>>> ticks).
>> David, do you have a reference for your "risks lost ticks" statement
>> as applied to Windows?
>> Thanks,
>> David
> ISTR that there have been previous references in this newsgroup.
> Specifically, EIDE disk drivers can mask or disable interrupts  for a
> period long enough  to cause a "lost tick".  I believe the group is
> archived somewhere. . . .

Thanks, Richard.  I can imagine that any disks working in PIO mode 
wouldn't be welcome friends either.  The last EIDE desktop PC I bought was 
some seven years ago, so I hope it's a problem which won't affect too many 
people, and all being well not those starting from scratch.


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