[etherlab-users] distributed clock offset ?

Yan Prochazka jprochazka at persimmontech.com
Sat Jan 26 03:12:27 CET 2013

Follow up:

it seems that, for whatever reason, the master writes not correct values 
to slaves system time offset registers (0x0920).
I *think*, if those would be correct, then master and slaves clocks will 
by in synchronization and SYNC0 pulses should occur at time passed to 
ecrt_master_application_time() adjusted by sync0_shift_time used in 
ecrt_slave_config_dc() call. Am I correct ?

On 1/25/2013 13:17, Yan Prochazka wrote:
> Hello Everybody!
> we currently use 1.5.0 version of EtherCAT master and Distributed Clock
> enabled slaves. Our application runs in user space and uses ecrt.h. DC
> synchronization seems to work perfectly, SYNC0 on all slaves and our
> application is kept in sync nicely, BUT how could I get, in my
> application, the absolute time offsets between time passed cyclically to
> ecrt_master_application_time() and absolute time of a particular slave
> when SYNC0 pulse is generated ?
> basically, there are an event generated on the slave at arbitrary time,
> I can get slave time of that event, but I need *somehow* match that
> slave time with SYNC0 time occurrence and with my application time.
> Therefore I need to know offsets between my application time and SYNC0
> absolute times on the slaves.
> Does anybody have any ideas or at least hints where and what to look for ?
> Thanks a lot,
> Jan Prochazka
> _______________________________________________
> etherlab-users mailing list
> etherlab-users at etherlab.org
> http://lists.etherlab.org/mailman/listinfo/etherlab-users

More information about the Etherlab-users mailing list