在下面横线上填上合适的语句，完成BCD-7段LED显示译码器的设计。 LIBRARY IEEE ; USE IEEE.STD_LOGIC_1164.ALL; ENTITY BCD_7SEG IS PORT( BCD_LED : IN STD_LOGIC_VECTOR(3 DOWNTO 0); LEDSEG : OUT STD_LOGIC_VECTOR(6 DOWNTO 0)); END BCD_7SEG; ARCHITECTURE BEHAVIOR OF BCD_7SEG IS BEGIN PROCESS(BCD_LED) 1 IF BCD_LED="0000" THEN LEDSEG<="0111111"; ELSIF BCD_LED="0001" THEN LEDSEG<="0000110"; ELSIF BCD_LED="0010" THEN LEDSEG<=“1011011”; ELSIF BCD_LED="0011" THEN LEDSEG<="1001111"; ELSIF BCD_LED="0100" THEN LEDSEG<="1100110"; ELSIF BCD_LED="0101" THEN LEDSEG<="1101101"; ELSIF BCD_LED="0110" THEN LEDSEG<="1111101"; ELSIF BCD_LED="0111" THEN LEDSEG<="0000111"; ELSIF BCD_LED="1000" THEN LEDSEG<="1111111"; ELSIF BCD_LED="1001" THEN LEDSEG<="1101111"; ELSE LEDSEG<= 2 ; END IF; END PROCESS; END BEHAVIOR;

填空部分应该是：

1. BEGIN
2. ELSE LEDSEG<="1111110";
3. END IF;

完整代码如下：

LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;

ENTITY BCD_7SEG IS
    PORT(
        BCD_LED : IN STD_LOGIC_VECTOR(3 DOWNTO 0);
        LEDSEG  : OUT STD_LOGIC_VECTOR(6 DOWNTO 0)
    );
END BCD_7SEG;

ARCHITECTURE BEHAVIOR OF BCD_7SEG IS
BEGIN
    PROCESS (BCD_LED)
    BEGIN
        IF BCD_LED = "0000" THEN
            LEDSEG <= "0111111";
        ELSIF BCD_LED = "0001" THEN
            LEDSEG <= "0000110";
        ELSIF BCD_LED = "0010" THEN
            LEDSEG <= "1011011";
        ELSIF BCD_LED = "0011" THEN
            LEDSEG <= "1001111";
        ELSIF BCD_LED = "0100" THEN
            LEDSEG <= "1100110";
        ELSIF BCD_LED = "0101" THEN
            LEDSEG <= "1101101";
        ELSIF BCD_LED = "0110" THEN
            LEDSEG <= "1111101";
        ELSIF BCD_LED = "0111" THEN
            LEDSEG <= "0000111";
        ELSIF BCD_LED = "1000" THEN
            LEDSEG <= "1111111";
        ELSIF BCD_LED = "1001" THEN
            LEDSEG <= "1101111";
        ELSE
            LEDSEG <= "1111110";
        END IF;
    END PROCESS;
END BEHAVIOR;