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Altera_Forum
Honored Contributor
13 years agolpm functions with no clock
Hi I am very new to fpga so apologise if these are dumb questions but I have searched all over and cant find any help. We are trying to use some lpm functions concatenated together, a mul...
Altera_Forum
Honored Contributor
13 years ago --- Quote Start --- from the doc lpmmult_accum is not a y = a*b+c operation, but it actually y = y + a*b, with y being an internal register within the function. Hence my question... --- Quote End --- You are right, y = y + a*b can't be implemented without a clock. Also the MegaWizard GUI doesn't have an option to omit the clock for the accumulator register. In the pdf user guide integer arithmetic megafunctions, ALTMULT_ACCUM clock inputs are designated as optional. This is probably just a typo, or referring to a special case where accumulator feedback is disabled.