[etherlab-dev] 1 datagram UNMATCHED! / working counter changes

Florian Pose fp at igh-essen.com
Fri Jul 31 10:40:33 CEST 2009


> I am currently performing some realtime tests with a PowerPC 1.5 GHz. Loop
> is running at 10 kHz (100us). Here is my EtherCAT topology:
> 
> PowerPC -> EK1100 -> EL4732 -> EL4732 -> EL4732
> 
> The logical process image comprises 12 Byte only (4 Byte per analog out
> slave).
> 
> Problem now is, that  I get error messages from the domain approx. every
> second (I am checking the domain state with every cycle, so every 100us):
> 
> EtherCAT WARNING: 1 datagram UNMATCHED!
> EtherCAT: Domain 0: 2 working counter changes - now 3/3.
> Domain1: WC 0.
> Domain1: State 0.
> Domain1: WC 3.
> Domain1: State 2.
> 
> I also sniffed the Ethernet packets with an ET2200 but could not find any
> errors. A packet with LWR datagram leaves every 100us (with WC 0) and about
> 2us later it returns after being proccessed by all slaves (with WC 3).

Does this mean, that the sniffer does not see any frame with unanswered
datagrams, or do you see datagrams with working counter 0 when the frame
comes back from the bus?

I guess the first one is the case, that would fit to the unmatched
datagrams. I must admit that I did not experience this before. Unmatched
datagrams mean that a received datagram could not be assigned to a sent
one. Could you please post the logs with 'ethercat debug 2' (be careful,
this will blow up your logs, please post only the interesting parts,
when an unmatchable datagram is received). If this gives us no hint, we
could enable the debug ring with --enable-debug-ring and output it when
an unmatched datagram appears...

-- 
Best regards,
Florian Pose

http://etherlab.org



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