Re: [RTnet-developers] Suspect packet

[Frank T. <fr...@fr...>]

> 
> Frank Tkalcevic wrote:
> >>> I'm not sure why the sync packets were coming out as well
> >> as the rtcfg
> >>> traffic.  Is that correct behaviour?  I would have 
> thought the sync 
> >>> process would only happen after rtcfg set up was complete.
> >> It is correct, RTmac/TDMA is in charge of managing the 
> media access 
> >> right from the start (that's why RTcfg stage 1 frames have 
> to include 
> >> all information a slave needs to send its own frames, 
> namely the TDMA 
> >> cycle offset and phase).
> >>
> >> BTW, Wireshark is capable of decoding RTnet frames, maybe 
> helpful for 
> >> understanding the procedures.
> > 
> > 
> > That's confusing me a bit.  It looks like rtcfg just 
> outputs packets 
> > as it pleases and doesn't obey real time rules.  Does it 
> sit on top of Rtmac?
> > Does it need to stop after all the clients are ready and 
> obeying the 
> > TDMA protocol, or can it coexist?
> 
> RTcfg is plain payload from RTmac/TDMA POV. Check if RTcfg 
> frames sent by the master have a fixed offset (minus jitter) 
> from the Sync frame. If not, something is badly configured 
> (but that is unlikely if you used the standard setup script).

Things are working fine.  The questions are for my understanding of rtnet.
Sorry for being a pest.

How is the offset defined?  In my stage 1 configuration I have...

TDMACFG rteth0 slot 0 200;ifconfig vnic0

which defines one slot at an offset of 200.  Is this used for rtcfg?  How
does the slave know at what offset to send rtcfg messages?  


Thanks,
Frank