Changes between Version 1 and Version 2 of AdderVbe

Timestamp:

Apr 8, 2007, 11:46:29 AM (17 years ago)

Author:

alain

Comment:

--

AdderVbe

@@ -4 +4 @@
 ENTITY  adder IS
   PORT (
-    i0          : IN  BIT_VECTOR(3 DOWNTO 0);
-    i1          : IN  BIT_VECTOR(3 DOWNTO 0);
+    x           : IN  BIT_VECTOR(3 DOWNTO 0);
+    y           : IN  BIT_VECTOR(3 DOWNTO 0);
     q           : OUT BIT_VECTOR(3 DOWNTO 0);
     cin         : IN  BIT;
@@ -21 +21 @@
 
 carry(0) <= cin;
-carry(4 DOWNTO 1) <= ( ( i1(3 DOWNTO 0)    AND i0(3 DOWNTO 0) )    OR
-                       ( i0(3 DOWNTO 0)    AND carry(3 DOWNTO 0) ) OR
-                       ( carry(3 DOWNTO 0) AND i1(3 DOWNTO 0) )    ) ;
-q       <= i0 XOR i1 XOR carry(3 DOWNTO 0) ;
-cout    <= carry(2);
+carry(4 DOWNTO 1) <= ( ( x(3 DOWNTO 0)    AND y(3 DOWNTO 0) )    OR
+                       ( x(3 DOWNTO 0)    AND carry(3 DOWNTO 0) ) OR
+                       ( carry(3 DOWNTO 0) AND y(3 DOWNTO 0) )    ) ;
+q(3 DOWNTO 0)      <= x(3 DOWNTO 0)  XOR 
+                        y (3 DOWNTO 0) XOR 
+                        carry(3 DOWNTO 0) ;
+cout    <= carry(4);
 
 END;