誰能告訴我爲什麼這個代碼不能被模擬。行爲檢查語法是正確的。我試圖創建一個整數的二維數組,這是不變的。VHDL整數二維數組
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.all;
use IEEE.STD_LOGIC_ARITH.all;
--selection function 1
entity S1 is
Port (
i : in STD_LOGIC_VECTOR (5 downto 0);
o : out STD_LOGIC_VECTOR (3 downto 0));
end S1;
architecture Behavioral of S1 is
type matrix is array(0 downto 3, 0 downto 15) of INTEGER range 0 to 15;
constant m : matrix :=
((14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7),
(0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8),
(4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0),
(15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13));
signal row : STD_LOGIC_VECTOR(1 downto 0);
signal col : STD_LOGIC_VECTOR(3 downto 0);
begin
row <= i(5) & i(0);
col <= i(4 downto 1);
o <= conv_std_logic_vector(m(conv_integer(row), conv_integer(col)), 4);
end Behavioral;
解決方法:應該是(0到N)而不是(0 downto N)。錯誤消息不是很清楚。
當你說它不能模擬你是什麼意思?它不運行嗎?或者它產生無效的結果?我看到的一件事是,你將2D矢量定義爲0 downto 3.這應該是3 downto 0.我不確定當你做倒退時會發生什麼。 – Russell