3-8译码器,用VHDL语言写的,感觉用case 语句比IF 更易表达
1ibrary ieee ;
use ieee.std-logic-1164.all;
entity eda i s
port(
a,b,c:in std-logic;
d :out std-logic-vector (7 downto 0)
) ;
end eda;
architecture behaviour of eda is
begin
case (c,b ,a) is
when “000”=>d<=“0000000l”;
when “00l”=>d<=“00000010”;
when “0l0”=>d<=“00000100”;
when “011”=>d<=“0000l000”;
when “l00”=>d<=“000l0000”;
when “l0l”=>d<=“00l00000”;
when “l10”=>d<=“01000000”;
when others =>d<=“10000000”; end case;
end behaviour;
就是二进制转十进制呀。
=BIN2DEC(A1)
可能要加工具加载宏里的分析工具库加上