第二种 这是你的命名错误 把文件名改为 A.java 因为你里面的类是 pub
在上面的代码中，第29行引用了一个名为 clk 的对象，但是并没有声明这个对象。VHDL 编译器无法确定 clk 是一个信号还是一个变量，所以报出了错误。为了修复这个问题，应该在实体部分中声明 clk 对象，例如：这样，clk 对象就声明了，VHDL 编译器就可以识别这个对象了。
问VHDL :在函数的变量声明区域中无法识别的类型ENTypeScript 是一种由微软开发的静态类型编程语言，它是...
你那个+1错误的写成了+l。
Note that the components are declared but not defined in the example. The components would be defined as entity/architecture pairs. entity hello is port (clock, reset : in end hello; boolean; char : out character); architecture structural of hello is constant char_sequence : string := "...
Error (10482): VHDL error at Adder4.vhd(25): object "cIn" is used but not declared code: LIBRARY IEEE; USE IEEE.STD_LOGIC_1164.ALL; ENTITY Adder4 IS GENERIC(CONSTANT N: INTEGER := 4); PORT( a, b: IN STD_LOGIC_VECTOR(N...
t没有定义。注意第一个process中虽然定义了一个t，但是它是局部变量，而在40行的需要再定义一次t。
(thedefaultisfalse)andusethlistreadingcommandsshowninTable1-1on 3. IfthefileisnotaVHDlistorifenable_vhdllist_readerissettofalse,HDL Compilerreadsthedesign. Thissectioncontainsthefollowingsubsections: •SummaryofReadingMethods •UsingtheyzeandelaborateCommands •UsingthereadCommand •ReadingDesignsWithDe...
Concurrent signal assignments are concurrently active and re-evaluated when any signal on the right side of the assignment changes value. The re-evaluated result is assigned to the signal on the left-hand side. Supported types of concurrent signal assign
Allows synthesiser to decide whether to assign a 0 or a 1 for minimum systhesised logic circuit.VHDL Data Types ● std_ulogic ● Is an unresolved data type ● Declared in package STD_LOGIC_1164 of library IEEE. ● All data signals are of unresolved type by default. ...