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Altera_Forum
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16 years ago

Inefficient M9K RAM usage with FPOINT

Hi Folks- I'm using Cyclone III with NIOS2 and I need to include the Altera FPOINT custom instruction. My part has 66 M9K blocks. The RAM usage summary reports that FPOINT uses a total of 1084...
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Altera_Forum
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16 years ago

a memory block M9K can not be splitted

if your function uses only "N" bits out of total "M" bits a M9K block has, then the difference is lost or unuseable.

have a look here

memory blocks in the cyclone iii device family (http://www.altera.com/literature/hb/cyc3/cyc3_ciii51004.pdf)

On page 2 you will see the possible M9K configurations.

example, lets have a single M9K block setup as 512 x 10 bits out of total possible 512 x 18 this M9K block has. this means 512 x 8 bits are not used and you can not generate something else with these bits and bytes.