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Altera_Forum
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15 years ago

Can Quartus generate carry chains automatically?

Is Quartus able to infer Cyclone II carry chains automatically in synthesis from user Verilog code, or only within Altera's own library modules? I'm using 10.1SP1 web edition on Linux. I've wr...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

A further experimental observation:

Using '+' operator (with data more than 1 bit wide), or LPM_ADD_SUB module, results in COUT/CIN carry chains being used, even when Auto Carry Chains option is turned off.

So I'm still looking for an example where Auto Carry Chains option actually does something.