下面是一个简单的多路选择器,编译时候不通过,我应该怎么设置文件目录,还有编译的时候应该按照什么顺序以及应该注意什么,谢谢各位好心人 library ieee; use ieee.std_logic_1164.all; entity mux is port(a1,a2,a3,s0,s1 :in std_logic; outy ut std_logic); end mux; architecture behave of mux is COMPONENT MUX21A port(a,b,s:IN std_logic; y:OUT std_logic); END COMPONENT;SIGNAL tmp : STD_LOGIC; begin u1:mux21a PORT MAP(a=>a2,b=>a3,s=>s0,y=>tmp); u2:mux21a PORT MAP(a=>a1,b=>tmp,s=>s1,y=>outy); END ARCHITECTURE behave; library ieee; use ieee.std_logic_1164.all; ENTITY mux21a IS PORT(a,b,s:IN std_logic; y:OUT std_logic); END ENTITY mux21a; ARCHITECTURE one OF mux21a IS BEGIN PROCESS(a,b,s) BEGIN IF s='0'THEN y<=a;ELSE y<=b; END IF; END PROCESS; END ARCHITECTURE one; |