【发布时间】：2015-02-01 17:33:01
【问题描述】：
我对 VHDL ALU 代码有疑问。我必须用 4 位操作数做 4 个操作的简单 ALU。我正确地实现了这些操作并且它们运行良好。为了执行，我使用 E2LP 板。为了选择操作，我选择了 4 个 JOY 按钮，每个操作一个。问题是，当我按下按钮执行操作并按下它时，我希望结果保持在 LED 上，而我没有选择任何其他操作，但这并没有发生。对于前 5 个 LED，这可以正常工作，但上面的 3 个不行。这仅适用于一个操作。我的模拟结果是正确的。这是项目架构的代码。提前谢谢你。
---------------------------------------------------------------------------------- Control logic
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
Port ( --clk : in STD_LOGIC;
in_saberi : in STD_LOGIC;
in_mnozi : in STD_LOGIC;
in_ili : in STD_LOGIC;
in_rotiraj : in STD_LOGIC;
out_saberi : out STD_LOGIC;
out_mnozi : out STD_LOGIC;
out_ili : out STD_LOGIC;
out_rotiraj : out STD_LOGIC);
end upravljanje;
architecture Behavioral of upravljanje is
signal tmps : std_logic := '1';
signal tmpm : std_logic := '1';
signal tmpi : std_logic := '1';
signal tmpr : std_logic := '1';
begin
logika : process(in_saberi,in_mnozi,in_ili,in_rotiraj)
begin
if (in_saberi='0' and in_mnozi='1' and in_ili='1' and in_rotiraj='1') then
tmps <= in_saberi;
tmpm <= in_mnozi;
tmpi <= in_ili;
tmpr <= in_rotiraj;
elsif (in_mnozi='0' and in_saberi='1' and in_ili='1' and in_rotiraj='1') then
tmps <= in_saberi;
tmpm <= in_mnozi;
tmpi <= in_ili;
tmpr <= in_rotiraj;
elsif (in_saberi='1' and in_mnozi='1' and in_ili='0' and in_rotiraj='1') then
tmps <= in_saberi;
tmpm <= in_mnozi;
tmpi <= in_ili;
tmpr <= in_rotiraj;
elsif (in_saberi='1' and in_mnozi='1' and in_ili='1' and in_rotiraj='0') then
tmps <= in_saberi;
tmpm <= in_mnozi;
tmpi <= in_ili;
tmpr <= in_rotiraj;
elsif (in_saberi='1' and in_mnozi='1' and in_ili='1' and in_rotiraj='1') then
tmps <= tmps;
tmpm <= tmpm;
tmpi <= tmpi;
tmpr <= tmpr;
else
tmps <= '1';
tmpm <= '1';
tmpi <= '1';
tmpr <= '1';
end if;
end process logika;
out_saberi <= tmps;
out_mnozi <= tmpm;
out_ili <= tmpi;
out_rotiraj <= tmpr;
end Behavioral;
--------------------------------------------------------------------------
-- this is for operation add
entity sabirac is
Port ( clk : in STD_LOGIC;
data1 : in STD_LOGIC_VECTOR (3 downto 0);
data2 : in STD_LOGIC_VECTOR (3 downto 0);
saberi : in STD_LOGIC;
result : out STD_LOGIC_VECTOR (7 downto 0));
end sabirac;
architecture Behavioral of sabirac is
signal c : std_logic_vector (5 downto 0) := "000000";
signal tmp : std_logic_vector (7 downto 0) := "00000000";
begin
sabiranje : process(clk,saberi)
begin
if (saberi='0') then
tmp(0) <= data1(0) xor data2(0);
c(0) <= data1(0) and data2(0);
tmp(1) <= data1(1) xor data2(1) xor c(0);
c(1) <= (data1(1) and data2(1)) or (data1(1) and c(0)) or (data2(1) and c(0));
tmp(2) <= data1(2) xor data2(2) xor c(1);
c(2) <= (data1(2) and data2(2)) or (data1(2) and c(1)) or (data2(2) and c(1));
tmp(3) <= data1(3) xor data2(3) xor c(2);
if(data1(3) = data2(3)) then
c(3) <= (data1(3) and data2(3)) or (data1(3) and c(2)) or (data2(3) and c(2));
tmp(4) <= c(3);
tmp(5) <= c(3);
tmp(6) <= c(3);
tmp(7) <= c(3);
else
c(3) <= data1(3) xor data2(3) xor c(2);
tmp(4) <= c(3);
tmp(5) <= c(3);
tmp(6) <= c(3);
tmp(7) <= c(3);
end if;
else
tmp <= "ZZZZZZZZ";
end if;
end process sabiranje;
result <= tmp;
end Behavioral;
-----------------------------------------------------------------------------
entity mul is
Port (
clk : in STD_LOGIC;
pomnozi : in STD_LOGIC;
data1 : in STD_LOGIC_VECTOR (3 downto 0);
data2 : in STD_LOGIC_VECTOR (3 downto 0);
result : out STD_LOGIC_VECTOR (7 downto 0));
end mul;
architecture Behavioral of mul is
begin
mnozenje : process (clk,pomnozi)
begin
if (pomnozi='0') then
result <= std_logic_vector(signed(data1) * signed(data2));
else
result <= "ZZZZZZZZ";
end if;
end process mnozenje;
end Behavioral;
--------------------------------------------------------------------------
entity rotate is
Port ( clk : in STD_LOGIC;
rotiraj : in STD_LOGIC;
data1 : in STD_LOGIC_VECTOR (3 downto 0);
data2 : in STD_LOGIC_VECTOR (3 downto 0);
result : out STD_LOGIC_VECTOR (7 downto 0));
end rotate;
architecture Behavioral of rotate is
signal tmp : std_logic_vector (3 downto 0) := "0000";
signal tmp2 : std_logic_vector (7 downto 0) := "00000000";
begin
rotacija : process(clk,rotiraj)
begin
if (rotiraj='0') then
tmp <= std_logic_vector(rotate_left(unsigned(data1),to_integer(unsigned(data2))));
tmp2(0) <= tmp(0);
tmp2(1) <= tmp(1);
tmp2(2) <= tmp(2);
tmp2(3) <= tmp(3);
tmp2(4) <= '0';
tmp2(5) <= '0';
tmp2(6) <= '0';
tmp2(7) <= '0';
else
tmp2 <= "ZZZZZZZZ";
end if;
end process rotacija;
result <= tmp2;
end Behavioral;
--------------------------------------------------------------------------
-- Logic OR operation
entity logicko_ILI is
Port ( clk : in STD_LOGIC;
data1 : in STD_LOGIC_VECTOR (3 downto 0);
data2 : in STD_LOGIC_VECTOR (3 downto 0);
logili : in STD_LOGIC;
result : out STD_LOGIC_VECTOR (7 downto 0));
end logicko_ILI;
architecture Behavioral of logicko_ILI is
signal c : std_logic_vector (5 downto 0) := "000000";
signal tmp : std_logic_vector (7 downto 0) := "00000000";
begin
logicko : process(clk,logili)
begin
if (logili = '0') then
tmp(0) <= data1(0) or data2(0);
tmp(1) <= data1(1) or data2(1);
tmp(2) <= data1(2) or data2(2);
tmp(3) <= data1(3) or data2(3);
tmp(4) <= '0';
tmp(5) <= '1';
tmp(6) <= '1';
tmp(7) <= '1';
else
tmp <= "ZZZZZZZZ";
end if;
end process logicko;
result <= tmp;
end Behavioral;
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