Completato modulo TwoComplement

TwoComplement.vhd

@@ -2,30 +2,53 @@ library IEEE;
 use IEEE.STD_LOGIC_1164.ALL;
 
 entity TwoComplement is
-	generic(BITCOUNT : integer := 8);
+
+	generic(
+		BITCOUNT : integer := 8
+	);
+	
 	port(
 		DIFF_EXP_C2 : in std_logic_vector((BITCOUNT-1) downto 0);
-		DIFF_EXP_ABS : out std_logic_vector((BITCOUNT-2) downto 0);
+		DIFF_EXP : out std_logic_vector((BITCOUNT-1) downto 0)
 	);
+	
 end TwoComplement;
 
 architecture TwoComplementArch of TwoComplement is
-	signal S : std_logic;
-	signal M : std_logic_vector((BITCOUNT-2) downto 0);
-begin
-	S <= DIFF_EXP_C2(BITCOUNT-1);
-	M <= DIFF_EXP_C2((BITCOUNT-2) downto 0);
+
+	signal SIGN : std_logic;
+	signal DIFF_EXP_ABS : std_logic_vector((BITCOUNT-2) downto 0);
+	
+begin
+
+	SIGN <= DIFF_EXP_C2(BITCOUNT-1);
+	
+	C2_PROCESS : process(DIFF_EXP_C2, SIGN)
 	
-	C2 : process(DIFF_EXP_C2)
 	begin
+	
 		for i in (BITCOUNT-2) downto 0 loop
-			M(i) <= S xor M(i);
+			DIFF_EXP_ABS(i) <= SIGN xor DIFF_EXP_C2(i);
 		end loop;
+		
 	end process;
 	
-	--sommare 1 a M se S = '1'
+	SUM : process(DIFF_EXP_ABS, SIGN)
 	
-	DIFF_EXP_ABS <= M;
+		variable CARRY : std_logic;
+	
+	begin
+	
+		CARRY := SIGN;
+	
+		for i in 0 to (BITCOUNT-2) loop
+			DIFF_EXP(i) <= DIFF_EXP_ABS(i) xor CARRY;
+			CARRY := DIFF_EXP_ABS(i) and CARRY;
+		end loop;
+		
+		DIFF_EXP(BITCOUNT-1) <= CARRY;
+	
+	end process;
 
 end TwoComplementArch;