实体与元件说明的对比 entity kanda is port(a, b: in std logic; y: out std logic) end kand component kand port (a, b: in std I y: out std logic); end component实体与元件说明的对比 entity kand2 is port(a, b: in std_logic; y: out std_logic); end kand2; component kand2 port（a, b: in std_logic; y: out std_logic); end component;