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Altera_Forum's avatar
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

Yeah. I know I've used a lot of registers and some of my design does use heavy pipelines. But I've noticed a weird thing in my report.

It's that the LUT REGs are less than 1 percent and the dedicated registers are nearly run out of. I suppose the LUT REGs are the Registers inside the ALM and paired with ALUTs.

Why the tool didn't fully utilize those resources but resort to dedicated logic registers?