[time-nuts] WWVB PPS clock pulse ?

[Lenny Story]

Chris, (all),

Oh, your right... that is better...

-Lenny


On Wed, Mar 30, 2011 at 12:58 AM, Chris Albertson <albertson.chris at gmail.com
> wrote:

> On Tue, Mar 29, 2011 at 7:30 PM, Lenny Story <lenny at codematic.com> wrote:
> > All,
> >
> > Ok... so i'll just make it a rising edge pulse of ~500ms.  That should be
> > enough time for a linux box to detect it.
>
> I would vote for a non-symetric waveform so you can see if it is inverted.
>
> I don't think the pulse is detected by software.  It's an interrupt.
> The Linux PPS handler reads the clock and stores it.  Latter software
> that "reads" the PPS is given the stored time tag. I'm pretty sure the
> interrupt hardware is trigged by the edge.  Choose the length so a
> human (you) can detect it
>
> --
> =====
> Chris Albertson
> Redondo Beach, California
>