Priority Circuit with just IF statements.

architecture plainif of priority  is

begin

-- priority circuit, Y7 highest priority input

-- Y1 is lowest priority input

process (y1, y2,y3, y4, y5, y6, y7)

begin

dout <= "000;

if (y1 = '1') then dout <= "001"; end if;

if (y2 = '1') then dout <= "010"; end if;

if (y3 = '1') then dout <= "011"; end if;

if (y4 = '1') then dout <= "100"; end if;

if (y5 = '1') then dout <= "101"; end if;

if (y6 = '1') then dout <= "110"; end if;

if (y7 = '1') then dout <= "111"; end if;

end process;

end plainif;

By reversing the order of the assignments, we can accomplish the same as the elsif priority chain. 

In a process, the LAST assignment to the output is what counts.

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