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Altera_Forum's avatar
Altera_Forum
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13 years ago

incorrect variables synthesis or expected behavior for simple adder function

Sorry if this is redundant or stupid, I was not able to find similar question on the forum or even Google. Actually, Google yielded some thread where the below code is quoted as a valid example o...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Actually, output c is (!a[3],a[2..0]) which is correct.

A 'free' double-quoted string produces a std_logic_vector(0 to n), setting bit(3) to one

The following code will translate correctly: 

Constant ONE : std_logic_vector(3 downto 0) := b"0001" ;
c <= plus_s_s(a, ONE);