how to do in vhdl

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voho

Joined: 24 Feb 2004
Posts: 105

09 Nov 2005 14:05 how to do in vhdl

Hi all,

I have 2 inputs A and B and 1 output Q(14:0);
I want to do this in vhdl:

If a=5 and B=10 then Q=000001111111111

Thank's in advance

regards
voho

nand_gates

Joined: 19 Jul 2004
Posts: 907
Helped: 120

09 Nov 2005 14:59 Re: how to do in vhdl

Here is how to do it!!

Code:

library ieee;
use ieee.std_logic_1164.all;

entity my_logic is

port (
A : in std_logic_vector(14 downto 0);
B : in std_logic_vector(14 downto 0);
Q : out std_logic_vector(14 downto 0));

end my_logic;

architecture behave of my_logic is

begin -- behave
process (A,B)
begin -- process
if (a="000000000000101" and B = "000000000001010") then
Q <= "000001111111111";
else
Q <= "000000000000000";
end if;
end process;

end behave;

Kukaz

Joined: 09 May 2001
Posts: 30
Helped: 1

10 Nov 2005 9:21 Re: how to do in vhdl

OR SO

library ieee;
use ieee.std_logic_1164.all;

entity my_logic is

port (
A : in std_logic_vector(14 downto 0);
B : in std_logic_vector(14 downto 0);
Q : out std_logic_vector(14 downto 0));

end my_logic;

architecture behave of my_logic is
begin

Q <= "000001111111111" WHEN (a="000000000000101" and B = "000000000001010") ELSE "000000000000000";

end behave;

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maksya

Joined: 02 Jun 2005
Posts: 172
Helped: 13

11 Nov 2005 21:37 Re: how to do in vhdl

In my opinion, your code needs to be corrected this way:

...
A : in std_logic_vector(2 downto 0);
B : in std_logic_vector(3 downto 0);

...
Q <= "000001111111111" WHEN (a="101" and B = "1010") ELSE