谁能告诉我为什么不能模拟这段代码。行为检查语法是正确的。我正在尝试创建一个二维整数数组，它是恒定的。
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;
解决方案:应该是(0 到 N)而不是(0 到 N)。错误信息不是很清楚。
最佳答案
你需要一个更好的语法检查器。
GHDL 报告:
ghdl -a --ieee=synopsys nullrange.vhd
nullrange.vhd:18:7: too many elements associated
nullrange.vhd:18:7: range length is beyond subtype length
nullrange.vhd:18:7: too many elements associated
nullrange.vhd:18:7: range length is beyond subtype length
nullrange.vhd:19:6: too many elements associated
nullrange.vhd:19:6: subaggregate length mismatch
nullrange.vhd:20:6: too many elements associated
nullrange.vhd:20:6: subaggregate length mismatch
nullrange.vhd:21:6: too many elements associated
nullrange.vhd:21:6: subaggregate length mismatch
nullrange.vhd:17:10: default value length does not match object type length
ghdl: compilation error
(0 downto 3) 被称为“空范围”，它是合法的但没有成员。所以初始化聚合中的元素太多了……
关于arrays - VHDL 2D 整数数组，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21266555/