library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;

entity I2C_ALU is
port(	scl_i, sda_i : in std_logic;
		scl_o, sda_o : out std_logic;
		input1_addr : in std_logic_vector(6 downto 0);
		input2_addr : in std_logic_vector(6 downto 0);
		control_addr : in std_logic_vector(6 downto 0);
		result_addr : in std_logic_vector(6 downto 0));
end I2C_ALU;

architecture I2C_ALU_impl of I2C_ALU is

component ALU is port(
    a, b: in unsigned(15 downto 0);  -- two input numbers
    ctrl: in unsigned(3 downto 0);   -- opcode
    r: out unsigned(15 downto 0));   -- result
end component;

component slaveIn is
port( scl_i, sda_i : in std_logic;                      -- I2C SCL, SDA input
	  scl_o, sda_o : out std_logic;                     -- I2C SCL, SDA output
	  devAddr_i : in std_logic_vector ( 6 downto 0);    -- I2C address for this device
	  is16Bits_i : in std_logic;                        -- register size, 1: 16 bits, 0: 8 bits
	  data_o : out unsigned(15 downto 0));              -- register data output ( (7,0) for 8-bit register )
end component;

component slaveOut is
port( scl_i, sda_i : in std_logic;                      -- I2C SCL, SDA input
	  scl_o, sda_o : out std_logic;                     -- I2C SCL, SDA output
	  devAddr_i : in std_logic_vector ( 6 downto 0);    -- I2C address for this device
	  is16Bits_i : in std_logic;                        -- register size, 1: 16 bits, 0: 8 bits
	  data_i : in unsigned(15 downto 0));               -- register data input ( (7,0) for 8-bit register )
end component;

signal a, b, r : unsigned(15 downto 0);
signal ctrl : unsigned(15 downto 0);

signal scl_out, sda_out : std_logic_vector(0 to 3);

begin

	input1: slaveIn port map(scl_i, sda_i, scl_out(0), sda_out(0), input1_addr, '1', a);
	input2: slaveIn port map(scl_i, sda_i, scl_out(1), sda_out(1), input2_addr, '1', b);
	control: slaveIn port map(scl_i, sda_i, scl_out(2), sda_out(2), control_addr, '0', ctrl);
	alu_inst: ALU port map(a, b, ctrl(3 downto 0), r);
	result: slaveOut port map(scl_i, sda_i, scl_out(3), sda_out(3), result_addr, '1', r);
	
	scl_o <= scl_out(0) and scl_out(1) and scl_out(2) and scl_out(3);
	sda_o <= sda_out(0) and sda_out(1) and sda_out(2) and sda_out(3);

end I2C_ALU_impl;