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TSchu3's avatar
TSchu3
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10 months ago

Arria 10 M20k block usage- More block with less memory bits?

Hello I have a design that fits on the Arria 10 GX dev board with chip 10AX11552F4sI1SG which has 2713 M20K blocks. The total memory bits for this design are 36,171,984, all 2713 blocks are used. ...
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TruHy's avatar
TruHy
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10 months ago

Hmm, the number of bits mentioned doesn't seem correct. M20K represents 20Kbits = 1024*20 bits

To use all of 2713 M20K your design would need to use:

1024*20*2713 = 55562240 bits

To use all of 2131 M20K your design would need to use:

1024*20*2131 = 43642880 bits

Perhaps you got the array size or index calculation wrong?

TSchu3's avatar
TSchu3
Icon for Occasional Contributor rankOccasional Contributor
10 months ago

TruHy, you have hit the nail on the head. It doesn't make any sense.
I did not calculate any of those numbers. They were pulled directly from the fitter summary.
This is the nature of my question. How can only 32 million bits need 2845 blocks?