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Altera_Forum's avatar
Altera_Forum
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16 years ago

The problem of multi_cycle custom instruction

Hi!

I want to learn the multi_cycle custom instruction,so I write an code randomly.

but the instruction didn't work in the NIOS IDE.I cann't find the error of the code,please help me.

library ieee;

use ieee.std_logic_unsigned.all;

use ieee.std_logic_1164.all;

use ieee.std_logic_arith.all;

entity move is

port(dataa:in std_logic_vector(31 downto 0);

datab:in std_logic_vector(31 downto 0);

result:out std_logic_vector(31 downto 0);

clk:in std_logic;

clk_en:in std_logic;

start:in std_logic;

reset:in std_logic;

done:out std_logic);

end move;

architecture behave of move is

signal t:std_logic_vector(3 downto 0);

signal a:std_logic_vector(31 downto 0);

signal b:std_logic_vector(31 downto 0);

begin

process(clk,clk_en,reset)

begin

if(clk_en='1')then

if(start='1')then

a<=dataa;

b<=datab;

t<="0000";

elsif(t<"1111")then

if(clk'event and clk='1')then

a<=a+1;

b<=b+1;

t<=t+1;

end if;

end if;

end if;

end process;

process(t,a,b)

begin

if(t="1111")then

done<='1';

result<=a+b;

else

done<='0';

end if;

end process;

end behave;

thanks in advance!

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    This is only template for guidance(haven't checked syntax) 

    
library ieee;
use ieee.std_logic_1164.all;
 
entity move is
port(
      dataa:  in    std_logic_vector(31 downto 0);
      datab:  in    std_logic_vector(31 downto 0);
      result:  out  std_logic_vector(31 downto 0);
      clk:      in    std_logic;
      clk_en :in    std_logic;
      start:   in    std_logic;
      reset:   in   std_logic;
      done:   out std_logic
);
end move;
 
architecture behave of move is
 
signal t: std_logic_vector(3 downto 0);
signal a: std_logic_vector(31 downto 0);
signal b: std_logic_vector(31 downto 0);
 
begin
 
process(clk,reset)
begin
if(reset = '1')then
   a <= (others => '0');
   b <= (others => '0');
   t <= (others => '0');
   done <= '0';
   result <= (others => '0');
elsif(clk'event and clk='1')then
   if(clk_en = '1')then
 
     if(start = '1')then
          a <= dataa;
          b <= datab;
          t <= "0000";
          done <= '0';
          result <= (others => '0');
     end if;
 
      if(t < "1111")then
            a <= a+1;
            b <= b+1;
            t <= t+1;
            done <= '0';
      else
           done <= '1';
           result <= a+b;
      end if;
   end if;
end if;
end process;
 
end behave;