[etherlab-users] master fsm datagram

[Gavin Lambert]

On 12 December 2014 19:01, quoth Peter P:
> does anybody know how the master-fsm exactly works? The master 
> fsm datagram in my program times out/gets skipped even before I 
> activate the slave. I assume it has something to do with the 
> ec_fsm_master in the fsm_masater.h, is that correct?
> 
> How can it be that there is a problem with a datagram that 
> should be internal to the ethercat master?

All datagrams are external -- they're actual network packets (or technically
fragments of packets).  It's called the "master fsm" datagram simply because
it's the one owned and sent out by the master FSM.  As the master FSM is
responsible for determining the number and identity of the slaves on the
network, this is in fact the most likely one to fail if you have
communication problems.

The most likely issue (other than hardware or wiring failure) is that you
are trying to run faster than your network drivers/OS can handle.