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Altera_Forum's avatar
Altera_Forum
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12 years ago

how to have the right comparison result with quartus

Hi I have write a vhdl module of comparison, with quartus, I have add it to the architecture with SopcBuilder, and call it from nios. In nios I don't have right result, I don't know why?? h...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

are you using std_logic_signed or std_logic_unsigned? (neither of these are part of the VHDL standard btw).

In your code, Y will be 1 when A > 0, or 0 when A <= 0. If you are using std_logic_unsigned, Y will always be 1, unless A is 0.