Very high speed integrated circuit Hardware Description Language (VHDL) – is an industry standard hardware description language – description the hardware in language instead of graphic
VHDL 的构造体基本结构 p.271 表 4-28 architecture arch_name of entity_name is declarations and definitions; 说明部分 begin concurrent statement; 语句部分 end arch_name; 构造体语法要点：
