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library ieee;
use ieee.std_logic_1164.all;
library ieee;
use ieee.numeric_std.all;
entity sub_145 is
port (
result : out std_logic_vector(3 downto 0);
in_a : in std_logic_vector(3 downto 0);
in_b : in std_logic_vector(3 downto 0)
);
end sub_145;
architecture augh of sub_145 is
signal carry_inA : std_logic_vector(5 downto 0);
signal carry_inB : std_logic_vector(5 downto 0);
signal carry_res : std_logic_vector(5 downto 0);
begin
-- To handle the CI input, the operation is '0' - CI
-- If CI is not present, the operation is '0' - '0'
carry_inA <= '0' & in_a & '0';
carry_inB <= '0' & in_b & '0';
-- Compute the result
carry_res <= std_logic_vector(unsigned(carry_inA) - unsigned(carry_inB));
-- Set the outputs
result <= carry_res(4 downto 1);
end architecture;
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