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[strykaar]

Hi friends I am trying to implement memory using VHDL and below is the code for that. I have a limitation that my address bus has to be 19 bits wide and data bus 8 bits, I am getting the following errors in the order mentioned:

1. parse error, unexpected LIBRARY, expecting error or IDENTIFIER
2. Library IEEE is not declared.

these point out at the very beginning on the code :

USE library IEEE;
USE IEEE.STD_LOGIC_1164.all;

package RAM_package is
subtype addr is std_logic_vector (18 downto 0);
type MEM is array (524287 downto 0) of addr;
end RAM_package;

USE WORK.RAM_package.ALL;
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity ram_1 is
port (A : in std_logic_vector(18 downto 0) :="0000000000000000000";
CEB, WEB, OEB : out STD_LOGIC;
data : inout std_logic_vector(7 downto 0));
end ram_1;

architecture Behavioral of ram_1 is

signal i_bus : std_logic_vector(7 downto 0) := "00000000"; -- RAM internal data latch
signal mem : MEM; -- RAM data

begin
process begin

variable i: integer;

for i in 0 to 128 loop

wait until CEB = '0';

if WEB = '1' then --- read op

i_bus <= mem(A);

elsif WEB = '0' then -- write op
mem(A) <= data;
i_bus <= data;

else i_bus <= ( others => 'X');

end if ;
A<=A+1;
end loop;
end process ;

process (OEB, i_bus) begin -- control output drivers:
case (OEB) is
when '0' => data <= i_bus;
when '1' => data <= ( others => 'Z');
when others => data <= ( others => 'X');
end case ;
end process ;

end Behavioral;