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Altera_Forum
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14 years ago

Design doesn't fit because of insufficient LAB

Hi all, I did a lot of redesign to reduce the register count and ALUT count. But it still doesn't fit because of lack of LAB. Could anyone tell me something about LAB? What is that used for? ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

A LAB (Logic Array Block) is a block of (10, I thin) ALUTs.

The ALUTs in a LAB have some shared resources (global signals, interconnect) which add some restrictions.

Thus, it is possible that even if you have enough ALUTs, your design can't be fitted because the ALUTs can't be properly grouped into LABs.