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Does ALM mean "Adaptive logic module"?

www.altera.com/literature/ds/ds_nios2_perf.pdf‎ Jul 1, 2013 -

One ALUT is equivalent to about 1.25 LEs.

Does LE mean logic element and ALUT means adaptive look-up table?

Niklas Rosencrantz
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1 Answers1

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http://quartushelp.altera.com/10.0/mergedProjects/reference/glossary/def_alm.htm

The Adaptive Logic Module (ALM) is the basic building block of supported device families and is designed to maximize performance and resource usage. Each ALM, composed of two Adaptive Look-Up Tables (ALUT) ...

LE has meant "logic element" for many years, although what defines a logic element is not entirely static, in Altera-land is usually means a 4-input look-up table (sometimes called a 4-LUT) + a d-type flipflop (DFF).

Martin Thompson
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  • Do you have a reference for the Altera definition of the logic element? – Randomblue Oct 21 '13 at 18:09
  • Not a good one... This is as close as I got, but it looks out of date (Xilinx's devices stop at Spartan 2 in the table!): http://www.altera.co.uk/cgi-bin/device_compare.pl - it says `Altera's and Xilinx's basic building block is a 4-input look-up table (LUT), a flip-flop and some additional circuitry that Altera calls a logic element (LE) and Xilinx calls a logic cell (LC). ` – Martin Thompson Oct 22 '13 at 15:22