[Voyage-linux] Re: PPS kernel patches

[Mark Phillips]

Sorry, didn't mean to send this twice.

Mark

On Mon, 2007-12-24 at 09:19 -0500, Mark Phillips wrote:
> You have to patch the kernel with the NTP patches rather than with gpsd
> patches.
> 
> Get the kernel patches here
> ftp://ftp.kernel.org/pub/linux/daemons/ntp/PPS/
> 
> And a vague howto here http://etienne.favey.ch/ntp/
> 
> Thanks for looking at this.
> 
> Mark
> 
> On Mon, 2007-12-24 at 09:27 +0800, Kim-man 'Punky' TSE wrote:
> > Hi ,
> > 
> > But where can I get the 1PPS patch for Linux and instruction?  As far as 
> > I read gpsd documentation, it indeed support 1PPS as long as you have 
> > the proper equipment.
> > 
> > What is the different between gpsd support for 1PPS and the 1PPS patch 
> > for the time server?
> > 
> > Regards,
> > Punky
> > 
> > Mark Phillips wrote:
> > > Any thoughts/comments on this Punky?
> > >
> > >
> > >
> > > On Mon, 2007-12-10 at 14:33 -0500, Mark Phillips wrote:
> > >   
> > >> I have mine setup in a similar way but it is not a true time server in
> > >> that because of the lack of a disciplining kick on a regular basis it is
> > >> able to drift between time updates.
> > >>
> > >> The problem with NMEA time strings is that they tend to come in a
> > >> cluster and not at all every second or 3 seconds or 5 seconds. They come
> > >> along whenever the GPS processor has time to spit them out.
> > >>
> > >> The 1PPS pulse from the GPS system is not derived from the decoded data
> > >> but rather is an inherant component of the GPS signal along with the
> > >> 10KHz pulse and thus is more reliable.
> > >>
> > >> I'd still like to see a 1PPS patched kernel particularly as it would
> > >> then allow for connections to things like Frequency Standards and LORAN
> > >> RX's etc. Heck, one could even connect it up to the mains after a very
> > >> simple signal divider (trick used on clock radios etc) is added.
> > >>
> > >> Mark 
> > >>
> > >> On Thu, 2007-12-06 at 19:24 +0800, Kim-man 'Punky' TSE wrote:
> > >>     
> > >>> Hi guys,
> > >>>
> > >>> Forget to mention, I have setup voyage attached to Garmin GPS18/USB and 
> > >>> get NTP time sync'd.  Of course, this device is not PPS-capable, but it 
> > >>> works without any patch to the kernel and NTP daemon.   See my blog article:
> > >>>
> > >>>     http://www.punknix.com/?q=node/116
> > >>>
> > >>> Regards,
> > >>> Punky
> > >>>
> > >>> Mark Phillips wrote:
> > >>>       
> > >>>> Now I think about it, updating the gpsd package would also be useful for
> > >>>> this purpose.
> > >>>>
> > >>>> FYI, my NTP server is running Voyage on a Neoware N3000 thin client
> > >>>> (ebay $20). It has a 300MHz via processor in it as well as an IDE
> > >>>> interface which is now running a CF card. The GPS RX plugs into ttyS0
> > >>>> and I'm running gpspipe on ttyS1 to allow my Nixie tube clock to correct
> > >>>> itself.
> > >>>>
> > >>>> Mark
> > >>>>
> > >>>> On Fri, 2007-11-30 at 05:10 +0000, Clark wrote:
> > >>>>   
> > >>>>         
> > >>>>> Mark Phillips <g7ltt at ...> writes:
> > >>>>>
> > >>>>>     
> > >>>>>           
> > >>>>>> Hi all,
> > >>>>>>
> > >>>>>> Is there anywhere that I can register a feature request for adding PPS
> > >>>>>> to the kernel for use in NTP apps? This would be really handy I think.
> > >>>>>>
> > >>>>>> Thanks
> > >>>>>>
> > >>>>>> Mark
> > >>>>>>
> > >>>>>>       
> > >>>>>>             
> > >>>>> I would really like that too!  
> > >>>>>
> > >>>>> I have been using Voyage to try to create an NTP appliance  'cause the
> > >>>>> commercial ones are WAY beyond my budget!
> > >>>>>
> > >>>>> I appreciate the work on Voyage so far!
> > >>>>>
> > >>>>> Thanks!
> > >>>>>
> > >>>>>
> > >>>>> _______________________________________________
> > >>>>> Voyage-linux mailing list
> > >>>>> Voyage-linux at list.voyage.hk
> > >>>>> http://list.voyage.hk/mailman/listinfo/voyage-linux
> > >>>>>     
> > >>>>>           
> > >>>       
> > 
> > 
-- 



Mark Phillips, G7LTT/NI2O
Randolph, NJ