[time-nuts] Of rubidium life and piggy-bank anemia....

[Poul-Henning Kamp]

In message <475127AB.6010300 at xtra.co.nz>, Bruce Griffiths writes:

>You don't actually require a latch for each input as long as flag bits
>(one per input channel) are used to denote which transitions occurred at
>the latched count.
>The flag bits should be latched along with the count.

The latches are for resolving meta-stability issues between the two
clock domains.

>Using a PCI card is perhaps a recipe for planned obsolescence.
>If the input transition rates are relatively low (eg with PPS inputs)
>then an onboard microprocessor with a serial port has more than
>sufficient bandwidth to keep up.

Yes, but using a PCI card makes it possible to use the setup as
timebase for your computer as well :-)

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