Re: [Ptpd-devel] No sync, ptpd over WiFi

[Jan B. <jan...@ja...>]

2013/6/3 Drasko DRASKOVIC <dra...@gm...>
>
> Hi all,
> I am trying to synchronize two Pandaboards running Linux with ptpd2.
>
> I am starting on master side :
> root@master:~/ptpd/ptpd-2.2.2/src# ./ptpd2 -C -b wlan0 -D -W
>
> And then on slave side :
> root@slave:~/ptpd/ptpd-2.2.2/src# ./ptpd2 -C -b wlan0 -D -g
>
> However, even clocks seem not to obtain synchronization.
>
> I output PPS on the GPIO of the boards and observe offset between them
> with oscilloscope. I have remarked that offset wonders without much
> predictability.
>
> I am having the problems decoding the log below, so if anybody can
> help explaining what is happening and why is this issue appearing.
>

Hi Drasko,

this is strange. Are you using unmodified version of PTPd?

It looks like some other program regulates clock speed e.g. some ntp
client, NetworkManager or so. Check running processes.

It is also possible, that frequency adjustment does not work as
expected. It seems that it adjust 50 times faster; 100 ppm adjustment
means 5000 ppm in reality. You can try my drift test program.
https://github.com/j123b567/adjtimex-test/
and compare my results from PC to your results on Pandaboard.


Regards,
Jan