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Altera_Forum's avatar
Altera_Forum
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16 years ago

Quartus II 9.1 changes inference rules for altsyncram

Hi folks, I may have found an interesting "feature" that appeared in Quartus II 9.1: a VHDL constant ROM is not inferred as an altasyncram if its size is not a power of 2. This is not the ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

You could also try to force the ram type with a vhdl attribute

attribute ramstyle : string;

attribute ramstyle of ROM : signal is "M4K";

and see what happens.

BTW: I also continue to use Quartus 9.0 SP2 as 9.1 does not work correct for my project. The fitter starts and runs forever without producing any result. That doesn't really match up the 20% performance gain promised :D

Best wishes, Alex