[LinuxPPS] 1PPS Atom Ref Clock Not being Polled?

[Rodolfo Giometti]

On Wed, Jul 22, 2009 at 12:38:53AM -0700, K. Connolly wrote:
> On Wed, 22 Jul 2009, Udo van den Heuvel wrote:
>
>> Shortest route would be to use the ppsldisc tool.
>>
>>> I tried running ppsldisc and ntpd and nothing really changed. I got
>>> positive system messages and my signal shows up in ntpq, but again, it
>>> never gets polled...
>>
>> Strange.
>> Are you sure you killed all ldattach instances?
>
> Yep. killed all ldattach instances, killed ntpd. Run ppsldisc /dev/ttyS0  
> and get:
>
> Jul 22 16:34:11 nu1vme02 kernel: new PPS source serial0 at ID 0
> Jul 22 16:34:11 nu1vme02 kernel: PPS source #0 "/dev/ttyS0" added
>
> Then start ntpd (4.2.4p5): ntpd -g:
>
> Jul 22 16:36:27 nu1vme02 ntpd[27939]: ntpd 4.2.4p5 at 1.1541-o Tue Jul 21  
> 08:02:16 UTC 2009 (2)
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: precision = 1.000 usec
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #0 wildcard, 
> 0.0.0.0#123 Disabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #1 wildcard, 
> ::#123 Disabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #2 lo,  
> ::1#123 Enabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #3 eth0,  
> fe80::2e0:ff:fe13:282a#123 Enabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #4 lo,  
> 127.0.0.1#123 Enabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: Listening on interface #5 eth0,  
> 10.128.1.192#123 Enabled
> Jul 22 16:36:27 nu1vme02 ntpd[27940]: kernel time sync status 2040
> Jul 22 16:36:29 nu1vme02 ntpd[27940]: frequency initialized 5.274 PPM 
> from /var/lib/ntp/drift
>
> After a few minutes it syncs to a peer and does as listed in my previous  
> e-mail (i.e. appears to work fine, but no PPS polling occurs :( )
>
> Any further thoughts? Much appreciated.

Drop NTPD and try if the PPS signal reach your system. Use ppstest and
enable kernel debugging messages.

In these days I'm very busy with other issues but as soon as possible
I'm going to add an official serial port support for LinuxPPS into
kernel mainline in order to try to remove these ldattach/ppsldisc
problems.

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail: giometti at enneenne.com
Linux Device Driver                          giometti at linux.it
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