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Altera_Forum
Honored Contributor
Honored Contributorsigned/unsigned multipliers
I can't seem to find a way to instantiate a multiplier that will dynamically select between signed and unsigned multiplication. This is on a Cyclone II, but applies to other parts as well. Read...
Altera_ForumHonored Contributor
Honored Contributor --- Quote Start --- So your method involves sign extending both 9 bit inputs to 18 bit? This means, you need four multiplier blocks instead of one, not a useful suggestion, to my opinion. I would rather use signed/unsigned inputs with altmult_add, as previously said. --- Quote End --- This discussion has been more about theory than practicalilty. In practice, if you need to use all the bits of the multiplier input, then you have to use the signa/b inputs on the megafunction. But, if you have spare bits on the input, you can simply sign extend and not need any more multipliers, and avoid using the wizard.
