Re: PREEMPT_RT vs I-PIPE: the numbers, part 2

Paulo Marques
2005-06-23T14:49:12Z

Kristian Benoit wrote:
> [...]
> Your analysis is correct, but with 600,000 samples, it is possible that
> we got 2 peeks (perhaps not maximum), one on the logger and one on the
> target. So in my point of view, the maximum value is probably somewhere
> between 55us / 2 and 55us - 7us. And probably closer to 55us / 2.

I could provide some help here, by providing the schematics and firmware
for having a microcontroller do the pulse timing part. The schematics
should be extremely simple, and easy to build in a breadboard (no
soldering required) with standard parts from electronics resellers.

With a hardware solution we could measure the *actual* target latency
with sub-microsecond accuracy, and do some fun stuff too, like
triggering the pulse at random intervals in a given range, etc.

The microcontroller would then connect to the logger (or the HOST in
your setup, and avoid an extra computer) through a serial port to report
the measurements.

Is this something that could be useful, or do you think this is just
overkill?

--
Paulo Marques - www.grupopie.com

It is a mistake to think you can solve any major problems
just with potatoes.
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