LIBRARY ieee; USE ieee.std_logic_1164.all; architecture behavior of dff is begin p1 : process (set, reset, clk) is begin if set = '1' and reset = '1' then q <= 'X'; elsif set = '1' and reset = '0' then q <= '1'; elsif set = '0' and reset = '1' then q <= '0'; elsif set = '0' and reset = '0' and rising_edge(clk) then q <= d; end if; end process p1; end architecture behavior; <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>