18 lines
452 B
VHDL
18 lines
452 B
VHDL
library IEEE;
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use IEEE.std_logic_1164.all;
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-- entity of the halfadder
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-- 2 inputs, 2 outputs, both of type IEEE1164 std_logic
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entity halfadder is
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port (a_i : in std_logic;
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b_i : in std_logic;
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sum_o : out std_logic;
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cy_o : out std_logic);
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end halfadder;
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-- behavioral description of the halfadder given by two gates
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architecture behavior of halfadder is
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begin
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sum_o <= a_i xor b_i;
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cy_o <= a_i and b_i;
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end behavior; |