如何编写VHDL测试平台

Question

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity ripplecarry4bit is
    port( a,b: in std_logic_vector (0 to 4);
          cin: in std_logic;
          s: out std_logic_vector (0 to 4);
          cout: out std_logic);
end ripplecarry4bit;

architecture RC4 of ripplecarry4bit is
    signal c: std_logic_vector (0 to 2);
    component fulladder4bit is
        port( a,b,cin: in std_logic;
              s,cout: out std_logic);
    end component;
    begin
        fa0: fulladder4bit port map(a(0), b(0), cin, s(0), c(0));
        fa1: fulladder4bit port map(a(1), b(1), c(0), s(1), c(1));
        fa2: fulladder4bit port map(a(2), b(2), c(1), s(2), c(2));
        fa3: fulladder4bit port map(a(3), b(3), c(2), s(3), cout);
end RC4;

我写了这个VHDL代码，我想测试一下！ 你能解释一下如何编写一个测试平台（或者如果你知道一些关于web的指南你能把它链接到我吗？我搜索了但我没有找到任何具体的东西）？