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Altera_Forum
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14 years ago

Stratix III ALM in arithmetic mode

Hi everybody, In the Stratix III Device Handbook volume 1, figure 2-11 indicates that in arithmetic mode, one can use 3 inputs (dataa, datab and datac) for the 2 first ALUT and use the outputs of ...
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Altera_Forum
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14 years ago

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Basically, the synthesisor does what should be best for your design. overruling the synthesisor can be hard work.

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This is obviously true in arithmetic operations. But as I found out in Cyclone III tests, the synthesis tool doesn't take full advantage of arithmetic mode for non-arithmetic problems, e.g. by utilizing the carry chain. I guess, this may be also the case with Stratix ALM.

See: http://www.alteraforum.com/forum/showthread.php?t=27881