[LinuxPPS] Re: Mabe I get it now...

[Rodolfo Giometti]

On Fri, Aug 10, 2007 at 11:23:39AM -0600, clemens at dwf.com wrote:
> 
> > > It is quite common with ntp (and the oncore driver) to put the following
> > > in the dev file
> > > 
> > > ln -s /dev/oncore.serial.0 /dev/ttyS0
> > > ln -s /dev/oncore.pps,0    /dev/ttyS0
> > > 
> > > linking BOTH the serial and the pps  devices used by the code to the 
> > > same device.  This could equally well read
> > > 
> > > ln -s /dev/oncore.serial.0 /dev/ttyS0
> > > ln -s /dev/oncore.pps.0    /dev/lp0
> > > 
> > > if the parallel interface were being used for the PPS signal,
> > > the code expects it will be able to open these two devices.
> > 
> > Yes! In LinuxPPS you should do instead:
> > 
> >    ln -s /dev/oncore.serial.0 /dev/ttyS0
> >    ln -s /dev/oncore.pps.0    /dev/pps0
> > 
> OK, mabe I understand what you are saying now.
> Are you saying that /dev/pps0 is a 'new' (magic) device provided by linuxPPS
> to get at the PPS data.  In fact it is reading data from /dev/ttyS0,  (or 
> /dev/lp0
> if the PPS device were a parallel device) but has this new name.

If the PPS device was a parallel device you should do:

   ln -s /dev/oncore.parallel.0 /dev/lp0
   ln -s /dev/oncore.pps.0 /dev/pps0

> If one were to search sysfs, one would find it.

Yes! :)

Rodolfo

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