[LinuxPPS] Re: PPS support in Linux 2.6.23

[Rodolfo Giometti]

On Mon, Oct 15, 2007 at 05:42:08PM +1000, Phil Manuel wrote:
> Hi Rodolfo,

Hi.

> I have patched the latest 2.6.23 kernel with PPS support, but I am getting 
> confused with regards to what options I should have turned on, what modules 
> I should have at the end of the process and whether the NTPD does or 
> doesn't need to be patched to handle a PPS input.  We are using the Endrun 

The modules you can get depend on your kernel configuration.

You can compile PPS support as kernel built-in and you don't need to
take care of the modules at all. :)

However the kernel module you get is pps_core.ko.

> Technologies Praecis Ct as our reference clock, this runs well with the 
> palisade driver.  However we wish to run the unit in PPS mode.  I've been 
> using this http://time.qnan.org/#driver-pps as my reference but note it is 
> a year out of date.

Yes, LinuxPPS has changed a lot from it. :'(

Also the patch at http://time.qnan.org/linux2.6-pps/ntpd-nmea.patch is
not right for the latest LinuxPPS version. You have to modify the NTPD
driver as PARSE refclock, so you have to provide an option PPS device
for the driver which should be opened if the GPS data source is not a
PPS source too.

Here the parse doc page:

   http://www.eecis.udel.edu/~mills/ntp/html/drivers/driver8.html

> Our ultimate aim is to use PPS and NTP to set the clock on a server and 
> then use ptpd to update the clocks on clients. (Already doing this with in 
> palisade configuration).

I can't help you on this topic... maybe other redears of this ML can
do it.

Please, feel free to write again if you need more help and/or
explanations.

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti at enneenne.com
Linux Device Driver                             giometti at gnudd.com
Embedded Systems                     		giometti at linux.it
UNIX programming                     phone:     +39 349 2432127