The Quartus II software version 2.2 SP2 respects resource constraints for the dcfifo megafunction.
Article ID: 000073798 Content Type: Troubleshooting Last Reviewed: 09/11/2012
Why doesn't the Quartus® II software place my FIFO in the memory block type that I selected in the MegaWizard® Plug-In Manager?
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Description Due to optimizations made to the dcfifo megafunction in the Quartus II software version 2.2 SP1, the placement constraints you made in the MegaWizard may not be honored.