library ieee; use ieee.std_logic_1164.all; entity product_adder_subtracter is port ( mode : in std_ulogic; a, b : in std_ulogic_vector(31 downto 0); s : out std_ulogic_vector(32 downto 0) ); end entity product_adder_subtracter; <div align="center"><br /><script type="text/javascript"><!-- google_ad_client = "pub-7293844627074885"; //468x60, Created at 07. 11. 25 google_ad_slot = "8619794253"; google_ad_width = 468; google_ad_height = 60; //--></script> <script type="text/javascript" src="http://pagead2.googlesyndication.com/pagead/show_ads.js"> </script><br /> </div>