Monday, July 8, 2013

INFO:Xst:2261 - The FF/Latch XXX in Unit XXX is equivalent to the following XXX FFs/Latches, which will be removed

I got this error the other day and it really caused me a lot of frustration. I was only building a simple core too.
Anyway I found this AR which would lead me to solving it http://www.xilinx.com/support/answers/38239.htm

I was frustrated because I could synthesize the lower blocks with no trouble, but the second I put them all into a top level it synthesized half the design away.

The bottom line is a lot of my logic was synthesized out and I am unhappy. Turns out it had to do with my output and I was connecting it to the wrong place because the controller basically would need the output from a different signal.

the TLDR: If You get this you messed up your logic, possibly in a top level because of a sm controller

No comments:

Post a Comment