So I am trying to do a 4 bit adder and have ran into an error I can't seem to figure out.
Error (10430): VHDL Primary Unit Declaration error at adder1.vhd(3): primary unit "Adder1Vhd" already exists in library "work"
I have a project called 4 bit adder and inside that project folder is the .vhd file for Adder1.vhd. Here is the codes I have, if somebody could help me figure this out it would be greatly appreciated.
Adder4.vhd:
LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;
ENTITY Adder4 IS
GENERIC(CONSTANT N: INTEGER := 4);
PORT(
a, b: IN STD_LOGIC_VECTOR(N-1 DOWNTO 0); -- Input SW[7..4]: a[3..0] inputs,
-- SW[3..0]: b[3..0]
cIn: in std_logic;
sum: OUT STD_LOGIC_VECTOR(N-1 DOWNTO 0); -- Output LEDR[3..0]
cOut: OUT STD_LOGIC -- Output LEDR[4]
);
END Adder4;
ARCHITECTURE imp OF Adder4 IS
COMPONENT Adder1
PORT(
a, b, cIn : in STD_LOGIC;
sum, cOut : out STD_LOGIC);
END COMPONENT;
SIGNAL carry_sig: std_logic_vector(N-1 DOWNTO 0);
BEGIN
A1: Adder1 port map (a(0), b(0), cIn, sum(0), carry_sig(0));
A2: Adder1 port map (a(1), b(1), carry_sig(0), sum(1), carry_sig(1));
A3: Adder1 port map (a(2), b(2), carry_sig(1), sum(2), carry_sig(2));
A4: Adder1 port map (a(3), b(3), carry_sig(2), sum(3), cOut);
END imp;
Adder1.vhd(the file inside the Adder4 project folder):
library ieee;
use ieee.std_logic_1164.all;
entity Adder1Vhd is
port(
a, b, cIn : in std_logic;
sum, cOut : out std_logic);
end Adder1Vhd;
architecture imp of Adder1Vhd is
begin
-- Add two lines (one for sum and the other for cOut) of VHDL code here
sum <= (a xor b) xor cIn;
cOut <= (a and b) or (cIn and (a xor b));
end imp;