并行信号赋值语句(CONCURRENT SIGNAL ASSIGNMENTS) 条件/选择信号赋值语句(CONDITIONAL/SELECTED SIGNAL ASSIGNMENTS) 进程语句(PROCESS STATEMENTS) 块语句(BLOCK STATEMENTS) 元件例化语句(COMPONENT INSTANTIATIONS) 生成语句(GENERATE STATEMENTS)
NULL语句 函数调用语句 过程调用语句 VHDL语言的顺序语句 顺序语句和并行语句是VHDL程序设计中两大基本描述语句系列。顺序语句（SequentialStatements）用来实现模型的算法描述。并行语句（ConcurrentStatements）用来表示各模型算法描述之间的连接关系。这些语句从多侧面完整地描述数字系统的硬件结构和基本逻辑功能，其中包括通信的...
• if • case Examples of concurrent control statements are conditional signal assignments: entity control_stmts is port (a, b, c: boolean; end control_stmts; m: out boolean); architecture example of control_stmts is begin m <= b when a else c; end example; All possible cases must ...
1.并行语句(ConcurrentStatements) 常用的并行语句有信号赋值、条件 赋值和元件例化等语句。 1.信号赋值语句。 2.条件赋值语句。 上一页下一页 (1)信号赋值语句 基本格式如下: <信号><=<表达式> 例如:a<=b; 此语句表示把b的当前值赋给信号a。
正文: 1 VHDL简介 VHDL的全称为VHSIC硬件描述语言(VHSIC Hardware Description Language),VHSIC: Very High Speed Integrated Circuit 1.1 历史 1980 – 美国国防部设立一个基金,在VHSIC项目之下开设
Historically there have been two styles of writing "decision" statements in VHDL - concurrent and sequential. And you had to get them correct - you could not use a conditional signal assignment such as... z <= x when x > y else y; ...
Chapter 5: CONCURRENT STATEMENTS. 5.1 Process Statement. 5.2 Assertion Statement. 5.3 Concurrent Procedure Call Statement. 5.4 Conditional Signal Assignment Statement. 5.5 Selected Signal Assignment Statement. 5.6 Component Instantiation Statement. 5.7 Generate Statement. 5.8 Block Statement. 5.9 Exercises. ...
These two concurrent statements copy the internal versions of the output signals to the actual outputs. We need to operate on internal copies because VHDL doesn’t allow us to read entity signals with modeoutinside of the module. An alternative would have been to declarein_readyandout_validwith...
Concurrent signal assignment Component instantiation statements Generate statement END ARCHITECTURE <identifier>; 配置(一般用到仿真的条件当中) -用于在模型内进行联系 -联系一个实体和体系结构 -联系一个组件和实体-体系结构 -广泛应用在仿真环境中 -为设计选择提供灵活而又快速的途径 ...
We can write any concurrent statements which we require inside generate blocks, includingprocess blocks,component instantiationsand even other generate statements. For Generate Statement in VHDL The for generate statement allows us to iteratively create multiple instances of a code block. We use the for...