在下面横线上填上合适的语句,完成一个 10 线- 4 线优先编码器的设计。 LIBRARY IEEE ; USE IEEE.STD_LOGIC_1164.ALL; ENTITY CODER IS PORT (DIN : IN STD_LOGIC_VECTOR(9 DOWNTO 0); OUTPUT : OUT STD_LOGIC_VECTOR(3 DOWNTO 0) ); END CODER; ARCHITECTURE BEHAV OF CODER IS SIGNAL SIN : STD_LOGIC_VECTOR(3 DOWNTO 0); BEGIN PROCESS ( ) BEGIN IF (DIN(9)='0') THEN SIN <= "1001" ; ( ) (DIN(8)=’0’) THEN SIN <= "1000" ; ELSIF (DIN(7)='0') THEN SIN <= "0111" ; ELSIF (DIN(6)='0') THEN SIN <= "0110" ; ELSIF (DIN(5)='0') THEN SIN <= "0101" ; ELSIF (DIN(4)='0') THEN SIN <= "0100" ; ELSIF (DIN(3)='0') THEN SIN <= "0011" ; ELSIF (DIN(2)='0') THEN SIN <= "0010" ; ELSIF (DIN(1)='0') THEN SIN <= "0001" ; ELSE SIN <= ( ) ; ( ) ; END PROCESS ; OUTPUT <= SIN ; END BEHAV;