Is the clockevent resolution fine-grained enough?

[Marko Rauhamaa]

It would appear the new clockevent API has a one-nanosecond resolution.
It certainly looks sufficiently fine-grained, but I'm afraid it's too
coarse for some applications.

In our application, we need periodic clock interrupts at about 100ÂkHz.
If the (programmable) frequency must be rounded to the nearest
nanosecond, we have a cumulative error of

   100,000 * 0.5 ns/s = 50 Âs/s

We need to maintain the cumulative error within, say, 1 ms/day, or
11Âns/s. (The error is not measured against real time, but between
different parts of our hardware that are run off of the same clock.)

For our needs, we have built our own "clockevent" system that has a
nominal one-femtosecond precision. The nanosecond resolution would be
sufficient if there was a way to "nudge" the next interrupt by a
nanosecond from the interrupt handler.


Marko

-- 
Marko Rauhamaa      mailto:marko@xxxxxxxxxx     http://pacujo.net/marko/
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