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MegaFunction wizard doesn't seem to allow using Logic Cells for small
roms & rams in Cyclone 3 as it allows in Cyclone 2. I don't want to use a M9K for a small memory block. Anyway to get around this silly limitation ? Am I missing something ? TIA JimLink Copied
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Hi,
Using Quartus II 9.0SP2, the megawizard allows one to select LEs for RAMs but not ROMs. This seems to apply to all supported device families. Weird, I must say. Suggestions: a) hope for the best, ie, set it to "AUTO" and let the tools balance registers vs M9Ks b) do not use the ROM megafunction, use just plain HDL for your ROMs.- Mark as New
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On second thought, I think I just made sense on what's going on.
With RAM/ROM megafunctions, Quartus allows one to change MIF files and the quickly update the programming files without recompiling the entire design. However, this is only feasible when using dedicated memory blocks. Thus, the following restrictions are observed: a) ROM megafunctions (which have to have a MIF file) must use dedicated memory blocks b) RAM megafunctions that force the usage of LEs do not support MIF files So, you need to go with "b)" for any small ROMs and initialized RAMs
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