VHDL
Posted: 10 Mar 2015, 10:09Salve
ho bosogo di aiuto per correggere alcuni errori sul questo codice
grazie mille.
ho bosogo di aiuto per correggere alcuni errori sul questo codice
grazie mille.
- Code: Select all
library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.std_logic_arith.all;
use IEEE.std_logic_unsigned.all;
Package package_adder_multi is
function adder(a,b: in std_logic_vector ;cin:in std_logic) return std_logic_vector;
function multi(a,b: in std_logic_vector ;cin:in std_logic) return std_logic_vector;
end package_adder_multi;
package body package_adder_multi is
function adder (a,b :in std_logic_vector;cin :in std_logic ) return std_logic_vector is
variable sum:std_logic_vector(3 downto 0);
variable resto:std_logic;
variable state:bit_vector(2 downto 0);
generic (tr:time :=9 ns)
begin
P1:process
begin
c2:case state is
when "000" => sum<='0'after tr;
resto<='0' after tr;
when "010" => sum<='1'after tr;
resto<='0'after tr ;
when "001" => sum<='1'after tr;
resto<='0'after tr ;
when "100" => sum<='1'after tr;
resto<='0'after tr ;
when "111" => sum<='1'after tr;
resto<='1' after tr;
when "110 " => sum<='0' after tr;
resto<='1' after tr;
when "011" => sum<='0' after tr;
resto<='1' after tr;
when " 101" => sum<='0' after tr;
resto<='1' after tr;
when "11x " => sum<='x' after tr ;
resto<='1' after tr ;
when " x11 " => sum<='x' after tr ;
resto<='1' after tr ;
when " 1x1" => sum<='x' after tr ;
resto<='1' after tr ;
when others => sum<='x'after tr ;
resto<='x' after tr ;
and case c2;
return sum;
end process;
end function adder;
function multi1 (a,b :in std_logic_vector;cin :in std_logic ) return std_logic_vector is
variable multi:std_logic_vector(3 downto 0);
variable resto1:std_logic;
variable state:std_logic;
begin
generic (tr:time :=9 ns);
begin
if(a='0' or b='0'or cin='0')then
multi<='0' after tr;
resto1<='0' after tr ;
elsif(a='1' and b='1' and cin='1')then
multi<='1' after tr ;
resto1<='0' after tr;
elsif others('x')after tr ;
end if ;
return multi;
end function multi1;
end package_adder_multi;