Re: [lwip-users] Re transmission behaviour?

[Pomeroy, Marty]

But if i set the cycle time of the master slow, like 80ms and slower i
get an response and a retransmission of that response for every request.
 request ->
 <- response
 <- retransmission


Fred

Your reponse needs to be acknowledged, and the acknowledgment (Ack) for
your previous response is included in the next request.  As I understand
it, if there is no pending request, the master would eventually send an
Ack independently.  Generally for efficiency, the Master tries to wait
to see if another packet needs to be sent so it does not need to send an
independent Ack.  If you go to perhaps 300ms cycle time, you may see an
Ack from the Master on the wire.

In any case, try raising your retransmission timeout above your cycle
time.

Marty