[LinuxPPS] Using LinuxPPS for Event Counting

[Rodolfo Giometti]

On Mon, Sep 29, 2008 at 10:57:17PM -0300, Thiago Tiedtke wrote:

>    I'm using the LinuxPPS with ntp to adjust a pc clock, using the DCD pin to
>    catch the PPS signal from gps, and NMEA messages from a GPS Novatel DL4
>    ...and this is task is ok, my question is:
> 
>    I can use the LinuxPPS to "poll" other type of events, e.g., a
>    interruptor, or a photodiode ??

Yes.

>    By fact, i'm doing these tests, "catching" events with 1/1000s of
>    duration...but without the regularity from signal PPS (e.g. at each 1 sec
>    +/- 20ns) from a GPS device....
> 
>    This can be applied? What the "quality" of timestamp of each event?

Mmm... the "quality" is the one that a non real-time kernel can
do. LinuxPPS has been designed for current time estimation and the
time stamp recording has been optimized to accomplish this task, but I
don't know if this optiomization is enought for you. :) You should do
some measurements by yourself to answer the question. Surely you can
use it to record whatever-you-want's timestamps.

Ciao,

Rodolfo

-- 

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