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Altera_Forum's avatar
Altera_Forum
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12 years ago

Comparison of numeric_std.unsigned fails

Hi, I've just started learning VHDL and already experience the first "unsolveable" problems, Although I've done some research I wasn't able to solve this question myself, please don't be hars...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

The 'center < to_unsigned()' itself returns a boolean which doesn't comply with your specified unsigned return type.

The function specification always specifies an unconstrained returned object, but it is up to you to return a properly constrained object at the exit of the function.

You may want to get hold of a good introductory book to VHDL like e.g. "Circuit Design with VHDL" by Volnei A. Podroni.