Flow control

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Flow control

Postby Guest » Thu Nov 13, 2014 1:39 pm

If initFC2 has different value and FCI have different value,then which credit will be stored either FC1 credit or FC2 credit

Re: Flow control

Postby support » Fri Nov 14, 2014 2:59 am


According to the spec, the transmitter should maintain a register, "CREDIT_LIMIT" for each of the controlled quantities (P, NP and Cpl). This register is updated "for each FC update received" (section In other words, each time an InitFC1, InitFC2, or UpdateFC arrives. The CREDIT_LIMIT in effect is always the latest one that arrived.

Since InitFC2 packets are sent at a state later than InitFC1, it follows that if their values are different, the one in InitFC2 takes effect (until an UpdateFC arrives).

This sound like a question from a quiz or something... ;)

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