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Altera_Forum's avatar
Altera_Forum
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17 years ago

Not enough LABs after small change

I have a project that uses a system built by the SOPC builder. We weren't getting the perf we wanted, and the critical paths were through an adder in the "burst" wrappers added. So, we made our own b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Fitter is running on the previous design so I don't have GPK's answer yet.

Gmpstr, I looked at a few units. Overall, everything seems bigger. I went and compare settings between the old and new projects, and for analysis & synthesis made them the same. I'm running synthesis on the new design again.

Something odd I did notice was that in the old design, four altshift_taps megafunctions were inferred in the ddr2 high performance controller. In the new design, two are, and a divider is inferred. This doesn't count for the overall increase in area usage, but it's not clear to me why there would be that difference and makes me wonder if something similar is happening elsewhere.