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From: GARY AFDGA<mimotofr@y...>
Date: Mon Nov 21 11:23:53 CET 2005
Subject: [oc] Whisbone newbie questions?
Dear Wishbone experts,

I have read the wishbone b.3 specs. I would like to
ask a few questions.

1. In RULE 3.25 (page 40) it says:

"[CYC_O] MUST be negated no earlier than the rising
[CLK_I] edge that qualifies the negation of [STB_O]".

But, in the 3.2.1 SINGLE READ Cycle (page 47), in the
CLOCK EDGE 0, I read:

"MASTER asserts [CYC_O] and [TGC_O()] to indicate the
start of the cycle. MASTER asserts [STB_O] to indicate
the start of the phase".

And here comes my questions. If CYC_O MUST be negated
"after (no earlier than)" the rising [CLK_I] edge that
qualifies the negation of [STB_O] then, why are
negated STB_O and CYC_O at the same time in the
wishbone timings?. shouldn't be negated STB_O first
and CYC_O in the next clock cycle?. What am I
forgetting?.

Thanks a lot and best regards,

mimoto




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Follow up	Author
[oc] Re: Whisbone newbie questions?	Michael Hordijk