Error (10349): VHDL Association List error at mult16bit.vhd(41): formal "o" does not

library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

use IEEE.STD_LOGIC_ARITH.ALL;

use IEEE.STD_LOGIC_UNSIGNED.ALL;

library work;

use work.all;

entity mult16bit is

generic (

DATA_WIDTH : integer := 16

);

port(

a : in std_logic_vector(DATA_WIDTH-1 downto 0);

--PARAM

b : in std_logic_vector(7 downto 0);

--PARAM

c : out std_logic_vector((2*DATA_WIDTH)-1 downto 0)

);

end mult16bit;

architecture Behavioral of mult16bit is

signal right : std_logic_vector((DATA_WIDTH)+4-1 downto 0);

signal left : std_logic_vector((DATA_WIDTH)+4-1 downto 0);

signal left_shifted : std_logic_vector((2*DATA_WIDTH)-1 downto 0);

signal new_right : std_logic_vector((2*DATA_WIDTH)-1 downto 0);

begin

MULTIPLIER_right:entity work.mult8bit

port map(

a => a(7 downto 0),

b => b,

c => right

);

MULTIPLIER_left:entity work.mult8bit

port map(

a => a(15 downto 8),

b => b,

c => left

);

left_shifted <= left & "0000000" ;

-- left_shifted <= std_logic_vector("sll"(unsigned(left), 8));

new_right <= "00000000" & right;

c <= unsigned(new_right) + unsigned(left_shifted) ;

end Behavioral;

sir now i m getting this error please help me thanks

expression has 20 elements, but must have 16 elements File: /mult16bit.vhd Line: 41

expression has 16 elements, but must have 20 elements File: /mult16bit.vhd Line: 41