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级别:
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积分:699分 |
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注册:2006年08月13日
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请教!高手请进!
如下一段程序我用来实现正弦查找表的功能,可是在编译的时候总会出现编译错误,ERROR:HDLParsers:163 - "C:/Xilinx/rom/rom_vhdl.vhd" Line 43. Unexpected symbol read: ¡.请问这是什么原因?应该怎么样解决?谢谢!
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity rom_chdl is
port(Q:in std_logic_vector(7 downto 0);
DD:out integer range 255 downto 0);
end rom_chdl;
architecture Behavioral of rom_chdl is
signal D:integer range 255 downto 0;
begin
process(Q)
begin
case Q is
when"00000000"=> D<=255; when"00000001"=> D<=254;
when"00000010"=> D<=252; when"00000011"=> D<=249;
when"00000100"=>D<=245; when"00000101" =>D<=239;
when"00000110"=>D<=233; when"00000111" =>D<=225;
when "00001000"=>D<=217; when"00001001"=>D<= 207;
when "00001010" =>D<= 197; when "00001011"=>D< = 186;
when "00001100" =>D<= 174; when "00001101" =>D<= 162;
when "00001110"=>D<= 150; when "00001111" =>D<= 137;
when "00010000" =>D<= 124; when "00010001" =>D<= 112;
when "00010010" =>D<= 99; when "00010011" =>D<= 87;
when "00010100"=>D<= 75; when "00010101" =>D<= 64;
when "00010110"=>D<= 53; when "00010111" =>D<= 43;
when "00011000" =>D<= 34; when "00011001"=>D<= 26;
when "00011010" =>D<= 19; when "00011011"=>D<= 13;
when "00011100"=>D<= 8; when "00011101" =>D<= 4;
when "00011110" =>D<= 1; when "00011111"=>D<= 0;
when "00100000" =>D<= 0; when "00100001" =>D<= 1;
when "00100010" =>D<= 4; when "00100011"=>D<= 8;
when "00100100" =>D<= 13; when "00100101" =>D<= 19;
when "00100110" =>D<= 26; when "00100111"=>D<= 34;
when "00101000" =>D<= 43; when "00101001" =>D<= 53;
when "00101010" =>D<= 64; when "00101011"=>D<= 75;
when "00101100" =>D<= 87; when "00101101"=>D<= 99;
when "00101110" =>D<= 112; when "00101111" =>D<= 124;
when "00110000" =>D<= 137; when "00110001"=>D<= 150;
when "00110010" =>D<= 162; when "00110011" =>D<= 174;
when "00110100"=>D<= 186; when "00110101" =>D<= 197;
when "00110110" =>D<= 207; when "00110111" =>D<= 217;
when "00111000" =>D<= 225; when "00111001" =>D<= 233;
when "00111010" =>D<= 239; when "00111010" =>D<= 245;
when "00111011"=>D<= 249; when "00111100"=>D<= 252;
when "00111101" =>D<= 254; when "00111110" =>D<= 255;
when others = > null;
end case;
end process;
DD<=D;
END Behavioral;
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